Police in Pitt Meadows, B.C., are thanking "determined citizens" who rushed to help two teens after their car crashed into a water-filled ditch Tuesday night.

The Honda Civic was driving along the 12700-block of Woolridge Road when the 18-year-old female driver somehow lost control of the vehicle, which flipped and landed in the ditch.

Police say the 17-year-old passenger managed to undo her seatbelt but the driver lost consciousness and wasn’t able to get out of the vehicle.

“Police want to acknowledge the determination of the citizens who managed to get both occupants out before emergency personnel arrived on scene,” said Const. Amanda Harnett.

The 18-year-old was rushed to hospital but was pronounced dead a short time later. The passenger only suffered minor injuries.

The investigation into her death will be led by the BC Coroners Service.

“This is a truly tragic event,” Harnett said.