Two people are dead and three others were hurt after a serious collision involving five vehicles on Hwy. 48 near Sutton, Ontario Provincial Police say.

The collision occurred on the highway near Old Homestead Road just before 12 p.m.

According to Sgt. Kerry Schmidt, a number of vehicles are involved including multiple transport trucks and at least one SUV.

“It involves several transport trucks, several commercial vehicles, several vehicles as well,” Schmidt said in a video posted to Periscope. “It is a massive scene right now.”

Schmidt said two people were pronounced dead at the scene.

He said the collision was ‘one of the most devastating crashes I've seen in a long time.”

Ornge says that they have airlifted a ten-year-old boy to hospital and airlifted a second person who was trapped in a vehicle to Sunnybrook Hospital.

The boy was taken to St. Michael’s Hospital for treatment. He is now in serious but stable condition.

A third victim, an adult, was taken to local hospital with less serious injuries, York Regional paramedics said.

Georgina Fire Chief Ron Jenkins said it took nearly an hour and half for crews to pull open one of the damaged vehicles and extricate an injured adult.

He said two firefighters were taken to hospital for treatment of heat exhaustion.

The cause of the collision is not yet known.

The highway has been closed between Old Homestead Road and High Street. Schmidt said the closure could extend for the remainder of Thursday.