A teen was in critical condition Monday after a possible suicide attempt at a Brooklyn train station during the morning rush hour, according to MTA and NYPD officials.

The 15-year-old girl apparently jumped in front of a Manhattan-bound R train shortly after 9 a.m. at the 53rd Street station, but struck her head against the train operator's window and fell back onto the platform. She was rushed to Lutheran Medical Center with critical head injuries.

Miranda Hall, a 27-year-old Bay Ridge resident commuting to work, said she was in the front car when the young girl apparently leaped in front of the fast-moving train.

"You hear screams on the platform and you just hear the thud of the body," Hall said.

Hall said people came to the girl's aid before emergency crews arrived.

"Her legs were moving but her face was just covered in blood," she said.