A Manhattan man accused of stabbing his 80-year-old neighbor to death in the neighbor’s apartment told a 911 operator he had a “psychotic break” and “killed” him with a knife, according to prosecutors.

The district attorney’s office has charged Alon Riabichev, 45, with second-degree murder in the lethal stabbing of Lev Vayner, whom first responders found dead in his apartment on Overlook Terrace near West 184th Street in Washington Heights around 3:15 a.m. Monday. A judge ordered Riabichev held in jail Monday as he awaits his next court appearance, set for Friday.

A criminal complaint filed by the DA’s office says an NYPD officer responding to the scene discovered Vayner “covered in blood and laying unresponsive on the floor” of his home. Riabichev was sitting “further away” inside the apartment, the complaint states.

“I had some kind of psychotic break and I killed somebody a few hours ago,” Riabichev had allegedly told the 911 operator over the phone earlier Monday morning. “The knife is on the table.”

Emergency medical workers declared Vayner dead as a result of three stab wounds to his torso and neck, according to the complaint. Police said Tuesday the two men knew each other, but officials were investigating a potential motive for the assault.

An attorney for Riabichev could not immediately be reached.

NYPD data shows homicides and felony assaults in the 34th Precinct, which includes Washington Heights and Inwood, are both down so far this year compared to the same period last year. The precinct had two homicides through Nov. 23, down from six by the same date in 2024, and about 280 felony assaults, a decline of more than 10% from 315 in 2024.

Brittany Kriegstein contributed reporting.