Vancouver police believe speed was a factor in a crash on the Burrard Street Bridge that left one dead and two others seriously injured early Tuesday morning.

Police said an Audi R8 was travelling north on the crossing when the driver lost control, crossing over the centre line and colliding with a southbound taxi shortly before 1 a.m.

The Audi was sheared in half during the collision and was in pieces on either side of the bridge when officials arrived. It was also fully engulfed in flames.

The cab came to a stop in the middle of the spliced wreckage, and had extensive front-end damage.

Officers are still investigating the cause of the crash and have provided few details, but Sgt. Jason Robillard told reporters, "I can say that speed was definitely a factor in this accident."

Robillard said the lone occupant of the Audi died at the scene, while the 68-year-old taxi driver and a passenger in his 30s were rushed to hospital.

He added that first responders are praising a driver who stopped to help right after the collision, but did not provide more information on the Good Samaritan's actions.

The crash is Vancouver's 11th fatal collision of 2017, police said.

Yellow Cab's Carolyn Bauer told CTV News that the taxi driver has been with the company for 30 years, and that she hasn't been able to get an update on his condition. She said the driver picked up the passenger in Gastown, and the vehicle was hit head-on as it headed south on the bridge.

Witnesses reported a massive fireball visible across False Creek.

Brenden Zimmerman told CTV News he was sitting in his bedroom in a building nearby when he heard a car switching gears, a sound he took to mean someone was speeding along the bridge. Zimmerman said he often hears vehicles accelerating on the bridge but that this seemed "really excessive."

"Then I just saw a large explosion on the bridge… It was pretty crazy," he said.

He ran outside to see what happened.

Zimmerman said he initially thought it was a single vehicle, but soon realized it was actually two.

The bridge was closed to vehicles, pedestrians and cyclists for about 12 hours as officials examined the crash site and city crews plowed the snow off the lanes. It reopened shortly after 1 p.m.

The investigation is ongoing, and anyone who witnessed the crash, either from the ground or from a highrise nearby, is asked to contact police at 604-717-3012.

With a report from CTV Vancouver's Nafeesa Karim and Shannon Paterson