Police said they are looking for a man who allegedly shoved two people, including an 83-year-old man, onto the subway tracks at an Upper East Side station on Sunday.

The NYPD said the suspect first approached a 30-year-old man from behind on the southbound F and Q platform at the Lexington Avenue–63rd Street station around 11:30 a.m. and pushed him onto the tracks. Officials said the assailant then approached the 83-year-old and also shoved him onto the tracks.

According to the NYPD, the shovings were unprovoked.

Both victims were transported to New York-Presbyterian/Weill Cornell Medical Center, officials said. The younger victim is in stable condition and the older is in critical condition as of Monday morning, according to police.

The NYPD said the suspect fled the scene and has not yet been identified. The department published images of the person it’s seeking wearing a gray jacket with a red hood underneath and beige pants.

Last month, a man shoved a 55-year-old man onto the subway tracks at the Jay Street–MetroTech station in Downtown Brooklyn after an argument, injuring him, police said. The month before, another subway shoving at a Sunset Park station left a 35-year-old man with minor injuries. A 39-year-old man was later arrested in connection with that incident.

NYPD data shows major crimes in transit — including grand larcenies, felony assaults and robberies — are up 12.5% through March 1 this year, compared to the same period last year. Officials have said the increase is likely in part due to the frigid weather this winter driving more people underground.

The MTA has installed barriers at more than 100 subway stations in the last year to improve rider safety and prevent people from falling onto the tracks.

This story is based on preliminary information from police and may be updated.