Ottawa police are trying to determine what led to a deadly collision that left a 34-year-old female cyclist dead.

The cyclist was killed when she collided with an STO bus on Sussex Drive in downtown Ottawa and was dragged to her death just before 5 p.m. on Wednesday. Her identity will not be released until next of kin are notified.

Police say a preliminary investigation reveals the cyclist was heading northbound on a bike path on Sussex Drive when she crossed over a curb and entered a bus lane.

Although the 44-year-old male bus driver from Gatineau was not injured in the collision, he was transported to hospital as a precaution.

Police say alcohol and speed don't appear to be factors in the collision.

The incident closed Sussex Drive between King Edward Avenue and Boteler Street in both directions until about 9:40 p.m.

The collision is the latest in a series of incidents involving vehicles and cyclists.

In July, a 22-year-old cyclist died after suffering a serious head injury when he was struck by a vehicle on Ogilvie Road.

A few days earlier, five cyclists were seriously injured when they were struck by a minivan on March Road in Kanata.

It's also the second fatal collision involving an STO bus driver this summer.

A Gatineau bus driver was charged with careless driving and starting from a stopped position in a way that is not safe after a 55-year-old male pedestrian died from his injuries after he was hit by an STO bus in downtown Ottawa on June 30.

Police ask anyone who has information about the latest fatal collision to contact investigators at 613-236-1222 ext. 2481 or Crime Stoppers at 613-233-TIPS.