NEW YORK >> Every day, the tiny elevator in Building 11 of the Boulevard Houses in Brooklyn does what it was built to do.

It ferries tenants to the lobby as they start their morning commutes. It carries retirees down to run midday errands. And it brings residents back to their apartments after a twilight chat or an evening cigarette.

To enter the elevator, residents swing open the leaden door and as they board, perhaps they glance up at the convex mirror that reflects anyone behind them. Inside, it is easy to feel encased in the dim confines of the metal box.

The ride is quiet, even serene. It is a stark contrast from the cacophony of police sirens tenants have heard for years outside their home, the oldest housing project in East New York, long one of the city’s more violent neighborhoods.

But the ride up or down the six-story building is slow and it gives some passengers enough time to remember why the elevator will forever be tainted by what happened inside nearly four years ago.

On June 1, 2014, the elevator was the scene of a killing that defied explanation. After following two children into the elevator, an assailant stabbed a 6-year-old boy, Prince Joshua Avitto, to death and slashed a 7-year-old girl, Mikayla Capers, to within an inch of her life. It was a gruesome crime that pained many in the city, and focused public attention, however briefly, on the security problems that plague many of the developments operated by the New York City Housing Authority.

The vicious attack still haunts the people who day after day set foot in the elevator, if they take the elevator at all. And over the last few weeks, Building 11 has had to relive the killing, as Daniel St. Hubert, the man charged in the attack, stood trial in state Supreme Court, about 7 miles away in downtown Brooklyn.

Mikayla, now 11, testified in the case, facing the man who prosecutors say killed her best friend, known to everyone as P.J., and nearly killed her. Last week the jurors heard closing arguments and after an unusual one-week break, the panel is expected to begin deliberating on Monday. St. Hubert, 30, is charged with second-degree murder and attempted murder. He has a history of mental illness, and the trial did little to illuminate a motive for the killing.

But it resurrected gruesome memories of the attack and of the four-day search for the killer. The manhunt was stymied by the lack of a security camera in the elevator, and that, in turn, fueled an uproar and crystallized the neglect public housing tenants had felt for years.

After the killing, a security camera was placed in the elevator of Building 11 and it watches over the tenants. To many of them, though, it is a reminder of the horror that unfolded when no one was watching.

“The whole neighborhood really remembers,” said Chris, a fourth-floor resident who declined to give his last name. “We’re mortified about it.”

Some families moved out after the attack, spooked by P.J.’s killing. Those who remain still talk about where they were and what they saw.

Mike Worsley, a first-floor tenant, saw P.J. and Mikayla outside the building lobby, on their way to grab Icees from P.J.’s apartment on the sixth floor. About 10 minutes later, Worsley heard the screams: “P.J.! P.J.!” On the fourth floor, Chris’ two nieces, then 10 and 13, found P.J. in the elevator car in a pool of blood from what the medical examiner would determine were 11 stab wounds. Mikayla crawled out from the elevator with 16 wounds and a collapsed lung, and was hospitalized for nine days. The assailant had fled, dropping a bloody 8-inch knife on the way out.

“I’d never seen a police officer break down and cry,” Chris said of an officer at the scene. “He just bawled.”

Since the attack, residents have found some measure of comfort in the self-locking lobby door and the improved exterior lighting and cameras placed outside. They say the police patrol the area more often.

Even with the 5,600 cameras housing officials say have been installed in public housing developments since 2014, about 40 percent of elevators in the city’s 325 projects do not have surveillance cameras.

And the camera in the 15-square-foot elevator has become a daily reminder for parents to not leave their children unsupervised, even inside the building.

“They’re never by themselves,” Evita Worley, 55, said of her three grandchildren. “I think neighbors are now more secure with their children.”

On a recent visit to the building, a few tenants trickled in and out of the elevator with grocery bags from the mini-market on Stanley Avenue. In the lobby, the frame around the elevator door was plastered with flyers: safety guidelines, city youth employment programs, an outdated winter storm warning.

Opposite the elevator, above the 38 mailboxes, hung a flyer with a picture of P.J. wearing a graduation cap and gown. “Coming Soon,” it read. “Prince Joshua Avitto Community Center.” The two-story building, with a gymnasium and a dance studio named after Mikayla, is scheduled to open across the street in May.

That stretch of Schenk Avenue was renamed Prince Joshua Avitto Way in 2015. Next to the street sign bearing P.J.’s name, a community garden known as the Garden of Peace was built in his honor. And all around the neighborhood, shops and restaurants have pictures of P.J. on their walls.

“This building is his memorial,” said Worley, who has lived 10 years in the Boulevard Houses. “His spirit will always be here.”

P.J.’s family moved out a month after the attack. But on Palm Sunday, while the trial in her son’s killing was underway, Aricka McClinton paid a visit to the neighborhood for Mass. Outside Building 11, she was joined by P.J.’s godmother, Anabelle Alston, and aunt, Sherri Avitto.

“No matter what, everything comes back to this building,” said Avitto, 52, who lives down the street.

Alston, 55, showed dozens of pictures of P.J. on her phone: the time he dressed as Barack Obama for school, the time he hit a home run at a baseball game.

McClinton reminisced on P.J. and Mikayla’s friendship: Mikayla had taught P.J. to walk when he was 1 and they would make plans by shouting from their bedroom windows.

Then, McClinton pulled out her necklace with a charm of a boy’s head that read: “My Little Superman.”

P.J.’s mother now lives in the Chelsea Houses, a public housing complex in Manhattan, but she occasionally makes the trek to East New York to visit family and friends in Building 11.

“I take the stairs, not the elevator.”