Three people have injuries following a serious collision in Milton early Thursday morning.

At around 3:30 a.m., Halton Police responded to a crash on James Snow Parkway and Esquesing Line, north of Highway 401.

Police say a Walmart tractor-trailer was stopped at the intersection when a crash involving a pickup truck and an SUV occurred behind the tractor trailer.

The tractor trailer was struck from behind.

Three people were extricated from the pickup truck and SUV, police say.

The tractor trailer driver was not injured.

Two people were transferred to a trauma centre with serious, non-life threatening injuries and one person was taken to hospital with unknown injuries.

One of the vehicles was on fire but was quickly extinguished, according to police.

Police say there was poor visibility at the time of the crash due to foggy conditions.

James Snow Parkway is closed north of Steeles Avenue between Esquesing Line to Boston Church Road as police investigate.