A woman is in critical condition after being "forcibly shoved" into a moving subway train in New York City and then falling onto the tracks, police said.

A male suspect in the apparent random attack is being sought, police said.

The "horrific assault" occurred at the 53rd Street/Fifth Avenue station in midtown Manhattan midday Wednesday, NYPD Chief of Transit Michael Kaplan said during a press briefing.

The 30-year-old victim was standing on the platform while a train was pulling out of the station when she was pushed, "causing her head to strike the moving train," Kaplan said.

The victim then fell onto the tracks, at which point good Samaritans helped her back up on the platform and called 911, Kaplan said.

She was transported to a local hospital with head trauma and underwent surgery, Kaplan said. She is currently in critical condition and is "fighting for her life," he said.

It is unclear what led up to the assault, Kaplan said. Eyewitnesses are currently being interviewed and the victim has yet to speak to police, he said.

Police identified a suspect in the assault as Sabir Jones, 45. He is known to the police department in the subway system, Kaplan said.

Jones allegedly fled the location on foot and exited the turnstiles at West 53rd Street and Fifth Avenue, police said while releasing surveillance footage of the suspect. He has not yet been apprehended, Kaplan said.

Officials said they believe the woman was going to or from work when she was randomly attacked.

"In the past year, we have made tremendous progress on subway crime," Janno Lieber, CEO of the Metropolitan Transportation Authority, said during the briefing. "But that's no consolation to the family of this young woman."