Police said they saw a suspected impaired driver hit and critically hurt a cyclist in west Ottawa Thursday afternoon.

Ottawa paramedics said the 31-year-old man was hit around 2:20 p.m. on Carling Avenue near Archibald Street.

He suffered a life-threatening head injury and then had a seizure en route to hospital, where he was still unconscious in critical condition upon arrival.

Police said they were called to a nearby plaza with a report of an impaired driver when they saw the crash happen.

"There were two separate incidents, one at Hampton Park Plaza where there was a minor collision," said Sgt. Al Ferris of the Ottawa police. "The suspect and the vehicle fled from there down Carling and subsequently struck a cyclist."

That male driver in his mid-20s was arrested on the scene.

The silver Toyota Matrix involved in the crash suffered heavy damage to its windshield and remained on the scene hours afterward.

Police say Carling Avenue's eastbound lanes are closed between Kirkwood Avenue and Archibald Street while they investigate.

With a report from CTV Ottawa's Ellen Mauro