A man was taken to hospital after being found with serious injuries in North York overnight.

An off-duty Toronto police officer spotted the man collapsed outside a residential building on Keele Street, near Flamborough Drive, at around 3:45 a.m.

The man, believed to be in his early 20s, appeared to have head wounds and a hand injury and was also suffering from exposure to the cold.

He was taken to a trauma centre with serious, but non-life-threatening injuries, Toronto Paramedic Services said.

Police initially said they were investigating the incident as an assault, but later said they do not believe the incident to be suspicious.