Multiple people have been shot in a Brooklyn subway station and several undetonated devices were also found at the location, according to fire officials and law enforcement sources. They stress the investigation is preliminary.

The FDNY says it responded to a call for smoke at the 36th Street and Fourth Avenue station, which serves the D, N and R lines in Sunset Park around 8:30 a.m. and found multiple gunshot victims. No details were immediately available on the devices.

Information on a possible suspect also wasn't immediately known.

Several law enforcement sources say a man possibly dressed in clothing that resembles those worn by MTA workers threw some sort of device and opened fire.

Some of the wounded jumped on another train to flee to the next station, the sources said.

The NYPD warned New Yorkers to avoid the area and to expect emergency vehicles and delays.

Photos posted to social media showed people bloodied on the platform, and Citizen app footage showed a heavy law enforcement presence at the scene.

The MTA says trains on the D, N and R lines were delayed amid an unspecified investigation.