A woman suffered life-threatening injuries Friday morning when her bicycle collided with a car door and then slammed into a school bus in Dorchester, according to officials.

The accident happened around 9:40 a.m. near 1200 Dorchester Avenue and Hancock Street, according to Boston police.

The cyclist, who was not identified, was riding her bike when a car door swung open in front of her, according to WBZ News. She reportedly struck the open door and was tossed into the side of a nearby school bus.

During the investigation, police closed the roads to traffic and instructed motorists to seek an alternative route.

No kids were on the bus at the time of the crash, WBZ reported. No charges were announced as of Friday evening.