Disturbing details are emerging about the man accused of fatally stabbing 14-year-old Caleb Rijos as the teen walked to school last Friday. The suspect, 29-year-old Waldo Mejia, has a lengthy history of violent criminal behavior, leaving neighbors wondering why he was still on the streets.

Surveillance footage from November shows Mejia repeatedly attacking a neighbor’s doorbell camera with a knife. The neighbor, who had asked Mejia to stop ringing his doorbell at odd hours, described the escalation that followed.

“He kept ringing the bell, like 2 a.m. or 3 a.m.,” the neighbor said. Video shows Mejia attempting to dismantle the camera before returning with a knife. Mejia was arrested but released after pleading not guilty, alarming residents.

“The lady above got nervous, and me, too. Everybody,” said another neighbor.

The situation turned tragic last week when police say Mejia stabbed Caleb Rijos on Alexander Avenue. Officers found Mejia nearby, still holding the bloody knife.

Court records reveal a troubling pattern of violence:

“If that guy had been in jail, that kid would be alive,” his neighbor.

According to the Bronx District Attorney’s Office, Mejia had pleaded guilty to reduced charges in several cases and received sentences of time served.

Now, neighbors are relieved Mejia is finally behind bars.

“The good thing is they caught the guy. I feel better because of that,” the resident said.

Mejia is facing charges of murder, manslaughter and weapons possession.

Police are also investigating his possible connection to another recent stabbing.