A 23-year-old woman has died after falling from a moving party bus in downtown Vancouver.

Police say they received a report at about 9:30 p.m. on Saturday that the woman had fallen out of the vehicle at Burrard Street and West Hastings Street.

Investigators say that the bus, which was carrying about 24 people for a birthday celebration, was turning south on Burrard Street when the woman fell from an open door onto the road where she was struck by the bus.

The driver immediately stopped the bus after he was alerted by passengers.

Paramedics pronounced the woman dead at the scene.

Police say the bus driver is co-operating with the investigation.

Vancouver Police Department's Collision Investigation Unit is probing the circumstances that led to the incident.