An 18-year-old woman died on Sunday when the jet ski she was riding collided with a motorboat in Long Island waters, police said.

The teenager’s watercraft and a 35-foot Fountain Motor Boat crashed around 10:30 a.m. in Middle Bay waters, southeast of Parsonage Cove in Hempstead, Nassau County Police said.

The young woman was taken to a local hospital where she was pronounced dead.

She wasn’t immediately identified by authorities.

Homicide detectives are investigating.