A motorcyclist who hit a car at a St. Paul intersection over the weekend has died, authorities said Tuesday.

Tyrone Jackson Jr., 21, of St. Paul, died Monday night at Regions Hospital after the crash early Sunday evening at Maryland Avenue and Hazelwood Street.

Charges are pending against the car's driver, 26-year-old Macy L. Robinson, based on the results of toxicology testing.

Robinson failed a police-administered field sobriety test at the scene, according to a search warrant affidavit filed in the case. A preliminary breath test at the same time showed she had not been drinking, leading the officer to believe Robinson was "impaired by a substance other than alcohol" said the affidavit, which seeks to take a sample of her blood for testing.

Robinson said she was heading east on Maryland and making a left turn onto northbound Hazelwood toward her home up the block, when the motorcycle hit the rear passenger side of her car, police said.

The motorcyclist was "driving at a high rate of speed" and went "over the handlebars, into the air and then down on the street," said police spokesman Steve Linders. Jackson was not wearing a helmet, Linders said.