The NYPD have identified a person of interest after at least 17 people were injured in a mass shooting on a New York subway overnight.

A gunman in a construction vest and gas mask set off a smoke canister on a rush-hour subway train in Brooklyn before opening fire, as commuters fled the station and ran for their lives.

Some passengers collapsed to the pavement as they poured onto the platform of the 36th Street station in the Sunset Park neighbourhood.

US correspondent Michael Genovese told Gareth Parker on 6PR Breakfast authorities don’t believe the incident was a terror attack but couldn’t rule anything out, with one of the biggest police operations in New York since 9/11 assigned to investigate the attack.

“Imagine being on the way to work on a train and someone releases some sort of gas cannister, the carriage starts to fill up with smoke and then that same person starts firing, round after round,” Genovese said.

“You would be so confused, you would be terrified, and then the panic kicks in.

“There blood all throughout the carriage, throughout the platform as well.”

Press PLAY below to hear Michael Genovese’s full report on the shocking attack