Four people from Saskatoon are dead after a PT Cruiser went into a slough late Tuesday afternoon east of the city.

RCMP say that two officers driving to Humboldt came across the car about a half hour's drive east of Saskatoon on Highway 5 near St. Denis.

They said it appeared the driver lost control, hit the ditch and then rolled into a slough. The car was submerged to the top of the windows, which were entirely below the waterline.

The accident closed down the highway as officers tried to piece together what happened. 

The car was pulled from the water and towed to Saskatoon. Mud and debris still cloaked the outside of the Cruiser this morning.

fatal crash into slough

Four people died when this SUV crashed east of Saskatoon Tuesday. (Supplied by RCMP)

RCMP said four adults were found inside the car. There were two adult females, in their 70s, one man in his 80s and another man whose age is not known. All are believed to be from Saskatoon. RCMP are still trying to contact their families.

The Office of the Chief Coroner will do the autopsy on the female driver.

A woman in St. Denis says people in the rural community have complained about that stretch of road for years. The heavy volume of farm traffic and lack of shoulders makes it treacherous to travel.

"This is a hot topic because the highway is so narrow, there's lots of big truck traffic, the farmers need to use to get from fields," said Dianne Lepage.

"This is ridiculous, how many people have to pass away before something is improved on this highway? There's been accident upon accident on this highway."