A crash involving six semi-trucks and over 20 vehicles injured 40 people and sent 13 to hospital Saturday morning.

The incident occurred shortly after 10 a.m. on Highway 16 two kilometres west of Maymont, Sask.

RCMP believe a two-vehicle crash in the highway’s eastbound lane and extremely foggy conditions led to multi-vehicle collisions on both sides of the divided double-lane highway.

“It appears that initially there was a collision between vehicles traveling in the eastbound lane. Shortly after this occurred there was a second collision between vehicles in the westbound lane who slowed to view the eastbound collision,” RCMP Cpl. Cathy Walter wrote in a press release.

Several vehicles were either unable to stop before crashing into other vehicles or were forced into the ditch due to the foggy conditions.

North Battleford’s WPD Ambulance transported eight patients to Battleford Union Hospital, MD Ambulance transported four patients to Saskatoon, and STARS air ambulance brought one patient to Royal University Hospital.

RCMP said none of the injuries are believed to be life threatening.

Alcohol is not believed to be a factor and no hazardous goods were involved in the collisions.

Several tow companies are working together to clear the scene and RCMP expect both lanes to open shortly.

Maymont is located off Highway 16 between Saskatoon and North Battleford.