A man was critically injured when he was struck by a train in Williamsburg on Sunday afternoon, authorities said.

The unidentified victim, who appeared to have jumped, was hit by an L train at the Bedford Avenue station in Brooklyn about 4:10 p.m.

“A man jumped. He was taken out alive. He jumped right when the train was coming,” an MTA worker said.

He was taken to Woodhull hospital in cardiac arrest.