A Brooklyn woman was dragged by a train — then struck by a second — on Saturday morning inside Union Square station, police said.

The 21-year-old was on the No. 4/5/6 platform around 3:30 a.m. when she somehow became wedged between the subway and the platform, police said.

As the train pulled out of the station, she was unable to free herself and was taken along with the train.

Video obtained by cops shows the girl being dragged from the platform onto the roadbed, police said.

After falling onto the tracks she was then struck by an incoming southbound 6-train, authorities said.

The woman, whose identity was not immediately released, was pronounced dead at the scene.

No criminality was immediately suspected.