Waldo Mejia is accused of randomly killing Caleb Rijos as the boy walked to school Friday morning. At the time of the slaying, Mejia, 29, faced an ongoing criminal case for allegedly kicking a neighbor’s door and damaging their Ring doorbell in the suspect’s apartment building in Mott Haven.

The trouble in Mejia’s building on Alexander Ave. near E. 139th St. began when the 43-year-old neighbor was awoken around 4 a.m. by Mejia, who apparently didn’t have a key.

Mejia was pounding on the building’s front door and ringing the neighbor’s intercom, trying to get inside.

The next day, the neighbor encountered Mejia in the staircase and confronted him about the commotion.

“I said, ‘Listen, why you be [ringing] my door?’ ” the neighbor recalled. “You got no keys, ask for the super.”

That conversation apparently set Mejia off.

“Next day, he hit my door — boom!” the neighbor said. “Kicked it hard.”

Ring footage shows Mejia trying to remove his neighbor’s doorbell camera’s lens before getting frustrated about 7 p.m. on Nov. 27. He then angrily kicked the door before retreating upstairs. About 30 minutes later, he returned with a long kitchen knife and stabbed the camera multiple times, cracking it, the creepy footage shows.

Mejia was arrested for harassment and criminal mischief that day, but the charges are not bail eligible so he was cut loose after his arraignment in Bronx Criminal Court.

His quick release and return to the building unsettled his neighbor.

“I got nervous,'” the neighbor said. “I saw him. I said, ‘Oh, my God, this guy’s here.’ ”

Since then, the neighbor has made sure Mejia is not around before leaving home.

“Every time I go by the stairs — my wife is the same way — we had to check my camera to see if the guy left,” the neighbor told The News. “I don’t want nothing to happen to me!”

Neighbors had good reason to be scared of Mejia.

On Jan. 5, Mejia allegedly jumped a 38-year-old stranger heading down the stairs at the Third Ave.-E. 138th St. subway station a block from Mejia’s home, then knifed him in the left arm. The blade perforated the limb, cut an artery and entered the man’s chest cavity, according to a criminal complaint.

The victim needed lifesaving surgery, but he survived. The attacker got away.

Then about 9:30 a.m. on Friday, Mejia ambushed Caleb near E. 138th St. and Lincoln Ave., half a block from the subway attack and close to where the high schooler lived, according to cops

Mejia jammed a serrated kitchen knife twice into the boy’s chest, cutting through his heart and lung, according to cops. The teen ran off and called his father, begging his dad for help with his final breaths.

It took a day for cops to nab Mejia for the slaying. NYPD detectives conducted a 1,000-foot radius search of the area and checked pervious crimes involving knives “and got an interesting result,” NYPD Commissioner Jessica Tisch said at a Saturday news conference about the arrest in Caleb’s killing. “Just 750 feet away there was an earlier crime in which an individual stabbed a Ring camera.”

“When detectives showed the arresting officer in that case the images taken from Friday’s stabbing, she immediately recognized the perp as Mr. Mejia,” Tisch added.

“Officers now knew who they were looking for and where he lived. They obtained footage from the same Ring camera he had stabbed weeks prior and saw him leaving his residence a few minutes before Friday’s stabbing.”

Cops grabbed Mejia returning to his building in the first minutes of Saturday. He was wearing the same sneakers and pants he wore during the fatal stabbing about 15 hours earlier, cops said.

“And he was in possession of a bloody knife,” Tisch said.

Mejia has a long criminal history, including four unsealed arrests, Tisch said. Two of those arrests involved knives while a third involved a gun.

Mejia was ordered held without bail during his arraignment on murder charges in Bronx Criminal Court on Saturday. “My name is Waldo Mejia, so get ready to f—–g suffer along with me!” the suspect shouted during his chaotic court appearance.

The neighbor with the damaged Ring doorbell said he was shocked when police knocked on his door Saturday to tell him about Caleb’s killing.

“I feel bad for the mother,” he said. “It’s very bad.”

He mused Mejia might have stabbed him, too, if given the chance.

“You open the door, the guy comes with a knife, and then what? I’ll be dead,” the neighbor said.

“I feel good that the guy is in jail because, you know, I don’t want nothing to happen to nobody. … I feel good. Like, I feel a little safe now. I feel better, Man.”

Esther Sealy, 87, was walking west along E. 88th St. at Avenue L in Canarsie around 6:46 p.m. and stepped into the crosswalk when she was struck by the driver of a 2010 Honda Odyssey making a left turn onto E. 88th St. The 39-year-old driver hit the victim and then crashed into a parked 2007 Toyota Camry that was unoccupied, cops said.

The victim suffered severe trauma to the body and was transported by EMS to Brookdale Hospital where she died.

The driver remained on scene and there were no immediate arrests as cops continue to investigate the accident.

The victim lived two blocks away from the scene.

Badiul Jamal, 72, was arrested following an incident on Jan. 6 around 3:30 p.m. near 81st St. and 31st Ave. in East Elmhurst where he allegedly followed the youth numerous times and grabbed her hand. Jamal then took off northbound on 81st St.

The girl was not injured.

Jamal was charged with luring a child, stalking in the second degree and harassment in the first degree.

Waldo Mejia, 29, jumped young Caleb Rijos near the corner of E. 138th St. and Lincoln Ave. at about 9:30 a.m. Friday morning, jamming a serrated kitchen knife twice into the boy’s chest, cutting through his heart and lung, NYPD Chief of Detectives Joseph Kenny said.

The mortally wounded teen ran off down E. 138th St. toward Alexander Ave., where he called his father, begging for help.

“He told his father he couldn’t breathe and he was scared,” Bronx District Attorney Darcel Clark said Saturday. “His father heard him dying. It’s unfathomable to think about the level of this tragedy.”

Mejia was arrested early Saturday for stabbing Caleb to death, as well as for another random stabbing at the Third Ave. — E. 138th St. subway stop on Jan. 5.

The two separate attacks occurred about a half-block from each other. Mejia lives nearby, cops said.

Mejia, who was wearing a black hoodie, gray pants, black socks and white flip flops was walked out of the 40th precinct by cops Saturday afternoon where he cursed out reporters as he was placed in the backseat of a squad car.

“I don’t know what the f–k y’all doing here on this planet!” Mejia yelled to reporters. “Y’all f–k around and I’mma beat your a– like a f—ing adult when I catch y’all!”

Mejia has a long criminal history with four unsealed arrests, Police Commissioner Jessica Tisch said Saturday. Two of those arrests involved knives. A third involved a gun.

Mejia was busted in November after a 43-year-old resident of a building on Alexander Ave. and E. 139th St. in Mott Haven who “feared for his safety” reported Mejia for harassing him and banging on his door repeatedly. Mejia proceeded to stab the victim’s doorbell camera, damaging it, cops said.

He was arrested soon after the incident and charged with criminal mischief and released without bail. The charge was not bail eligible.

“He is a violent recidivist with documented mental health interactions with the NYPD,” Tisch said at a press conference at police headquarters Saturday. “Today, a 14-year-old boy is dead, a family is devastated, a city is in mourning and the systems we have in place to deal with repeat offenders and people with severe mental health issues continue to fail us.”

Prosecutors charged Mejia with murder, manslaughter and weapons possession. His arraignment in Bronx Criminal Court was pending.

The charges for the Jan. 5 attack were also pending, Clark said.

Caleb’s devastated father told the Daily News Friday night that his family was still trying to piece together what happened.

“He was a wonderful boy. He was caring and loving. It’s hard right now,” said Jacob Rijos, 52. “We’re discussing the next steps. The police are still doing their investigation. We don’t really know what happened.”

Caleb’s family declined to comment Saturday after Majia’s arrest was made.

“The detectives told us,” a relative mumbled through a closed door. “We just want our privacy now.”

Surveillance footage viewed by The News shows Caleb sprinting north on Lincoln Ave. past a Gasolina station before darting east along E. 138th St., his attacker hot on his heels.

The teen ultimately collapsed between two parked cars. Witnesses called 911 and EMS rushed the teen to Lincoln Hospital, but he couldn’t be saved.

A worker at the Gasolina station who is also a friend of the teen’s family overheard Caleb’s call to his father.

“He called his father saying, ‘Dad, I can’t breathe,’” said the friend, who asked that his name be withheld. “He was running and the other guy got him.”

Caleb didn’t deserve to die in the streets, the family friend said.

“It’s crazy. It doesn’t make sense,” he said. “He was a good kid. He always dressed nice. He wasn’t a street kid.”

Caleb was a student at Bronx Leadership Academy and played for the school’s football team, friends and neighbors said.

“That’s a baby. He’s still a baby,” a resident of Caleb’s building told the News. “It’s horrible. They be going to school now and that’s gonna happen to them?

“He was just beginning life,” she said somberly. “That really hurt me.”

Kenny said his detectives distributed surveillance images of the attacker to the public as well as all officers on patrol. A short time later, a transit cop said the man looked exactly like the suspect wanted for a Jan. 5 stabbing at the Third Ave.—E. 138th St. subway station.

In that case, a 38-year-old man was heading down the subway stairs heading to the No. 6 train, when the suspect jumped him from behind for no reason and stabbed him in the left arm, Kenny said.

The victim was taken to an area hospital, where he received stitches for the wound, cops said.

“A police officer from the transit bureau recognized the perpetrator from the Jan. 5 incident and notified detectives,” Kenny said during a press conference late Friday night. “We quickly realized that the two cases were similar.”

Detectives conducted a 1,000-foot radius search of the area and checked pervious crimes involving knives “and got an interesting result,” Tisch said.

“Just 750 feet away [from the killing] there was an earlier crime in which an individual stabbed a Ring camera,” she said.

That incident led police to Mejia.

“When detectives showed the arresting officer in that case the images taken from Friday’s stabbing, she immediately recognized the perp as Mr. Mejia,” Tisch said. “Officers now knew who they were looking for and where he lived. They obtained footage from the same Ring camera he had stabbed weeks prior and saw him leaving his residence a few minutes before Friday’s stabbing.”

Cops grabbed Mejia returning to his building just after 12 a.m. Saturday. He was wearing the same sneakers and pants he wore during the stabbing.

“And he was in possession of a bloody knife,” Tisch said.

While the area where Caleb was killed is known for gang activity, cops found no evidence that the teen had run with a gang.

“This was a young man on the right path in life and was tragically taken from his parents,” Kenny said.

Mejia’s arrest comes as Gov. Hochul plans to introduce legislation in the state budget that would make it easier to involuntarily commit those suffering from mental illness to hospitals.

When she made her announcement, Hochul cited an uptick in violent crimes on the NYC subway system — including an incident where a homeless woman was fatally set on fire aboard a Brooklyn F train.

Mayor Adams has supported Hochul’s legislation — and has called for changing the state’s civil commitment laws.

“We must stop being so idealistic that we’re not realistic,” he said.

Tisch said Caleb’s “senseless and tragic” death should be a “call to action” to take the violently mentally ill off city streets and give them the help they need.

“The status quo is not working for New Yorkers,” she said. “We do not have a system to put the rights and needs of citizens first.

“Something has to give,” she said.

The slasher got into a verbal dispute on Dec. 20 with a 50-year-old man on the staircase inside the York St. subway station at Jay and York Sts. in DUMBO around 11 p.m. The victim was first punched in the face and then slashed in the face.

EMS transported the victim to NewYork-Presbyterian Brooklyn Methodist Hospital, in Park Slope, in stable condition.

Photos released by cops show the person of interest wearing a black hoodie and gray sweatpants, with a gray backpack.

Police ask anyone with information to call the NYPD Crime Stoppers hotline at 800-577-TIPS.

Cops responding to a 911 call at 12:57 p.m. near E. 10th St. and Avenue O in Midwood found a 38-year-old man and a unidentified man believed to be in his 30s unresponsive inside a red four-door sedan parked by a hydrant in the middle of the block, sources and cops told the Daily News.

“The police said they had overdosed,” said a local woman who didn’t want her name used. “It’s crazy. I was just trying to keep my kids away from the scene.”

The Shomrim civilian patrol alerted the police when they discovered the bodies, sources said.

EMS pronounced both of the men deceased at the scene. Cops said there were no visible signs of trauma.

According to police, around 2:30 p.m., the woman was in the crosswalk at W. 36th St. and 9th Ave. when the SUV, traveling southbound on 9th Ave., barreled into her and drove off.

“She was crossing the street and the car came up and made a left turn and hit her,” said Tahani Awad, who works at 9th Ave. Deli and witnessed the incident. “I hope that lady is okay because she looked to be in bad condition.”

“The guy just took off, he didn’t even stop to check if she was fine or nothing,” Awad added. “That’s heartbreaking. It’s sad that you just left the lady on the street,.”

EMS transported the injured woman to Bellevue Hospital in serious but stable condition, according to police. The SUV fled the location and did not remain on scene.

An investigation is underway.

The two got into an argument around 11:20 a.m. near the Marble Hill Houses, at Broadway and W. 225th St., in Marble Hill. They then each pulled out a gun and fired at each other multiple times, though none of the shots connected, cops said.

One of the shooters fled southbound on Broadway while the other fled northbound along the avenue.

No one was injured in the incident, according to police.

Anyone with information in regard to this incident is asked to call the NYPD’s Crime Stoppers hotline at 1-800-577-TIPS (8477) or for Spanish.

More than 60 firefighters and EMS personnel responded to a private home around 3:05 a.m. near Avenue I and E. 37th St. in Flatlands. The fire erupted from the basement of the two-story building. The blaze was said to be under control by 3:48 a.m., according to the FDNY.

The victim was transported by EMS to Kings County Hospital in critical condition.

FDNY personnel are still conducting an investigation as to the fire’s cause.

Investigators in East Harlem handcuffed police officer Samuel Sierra, 35, around 7:30 p.m. Friday on charges of first-degree rape, strangulation and assault.

The NYPD said the attack was “domestic in nature” — meaning Sierra allegedly attacked a partner or family member — but wouldn’t disclose any further details.

Sierra pleaded not guilty at his arraignment Saturday afternoon in Manhattan Criminal Court, where he was ordered held with his bail status set at $50,000 cash, $100,000 insured bond or $100,000 partially secured surety bond.

The six-year member of the force, who earned more than $168,000 last year, joined the NYPD in 2018 and has spent most of his career patrolling the 77th Precinct in Brooklyn. He received a meritorious police duty award in 2019.

While on duty in February 2023, he was accused of assaulting a woman and abusing his authority during a traffic stop, according to the 50-a.org website. He was ordered to undergo retraining, although the abuse of authority and physical force allegations were deemed to be “within department guidelines.”

In December 2023, he was transferred over to the Auxiliary Police Section, where he helps oversee civilians who volunteer their time as auxiliary cops.