The first incident happened near Allen Road and Sheppard Avenue. A car rear-ended a tractor-trailer, sheering off an axle on the tractor-trailer and sending a set of tires flying, according to the police.
Firefighters had to use hydraulic rescue tools to free the two men trapped inside the car. They were rushed to hospital with serious injuries.
Allen Road will be closed for several hours between Transit Road and Sheppard Avenue for the investigation, police said.
Meanwhile, traffic is moving at Keele and Wilson once again after a cab and a car collided around 6 a.m.
Four people were sent to hospital, and two of them are in critical condition, according to the police.
No charges have been laid at this point.