Before the long weekend was over for many people, it had already been a deadly weekend on Saskatchewan highways.

Police were called to Highway 39, approximately five kilometres north of Milestone, Sask. Saturday evening.

A semi and a truck collided near Milestone around 5:30 p.m. CST.

The 16-year-old driver of the truck, who was from Moose Jaw, died at the scene. The Edmonton, Alta. semi-driver, 53, was not injured.

Both drivers were alone in their vehicles at the time of the crash.

An Unmanned Aerial Vehicle was used to photograph and reconstruct the scene.

RCMP are still investigating how it happened.

Second deadly Saturday crash

A second deadly crash happened north of Regina on Highway 6 shortly before midnight Saturday.

According to officers, an SUV and pickup truck heading in opposite directions collided. The driver of the SUV died at the scene.

Investigators say there was thick fog cover at the time and first responders were seen in the adjacent fields searching with flashlights.

Police believe alcohol was a factor in the crash.

Three serious crashes Friday    

These deadly collisions follow three other serious crashes that happened Friday on Saskatchewan roads.

The first deadly crash happened on Highway 20 near St. Benedict, Sask. just before 3 p.m. CST Friday.

One person died on scene after a vehicle collided with a gravel truck.

Two passengers were transported to hospital in Humboldt, Sask. with non-life threatening  injuries.

Later Friday evening, just before 8:00 p.m. CST, an 18-year-old man died in a rollover that happened on a grid road near Lac Vert, Sask.

Five others were taken to hospital in Melfort, two of which were later airlifted to hospital in Saskatoon by a STARS helicopter.

Alcohol is believed to be a factor in the crash.

Hours later, around midnight, police were called to a highway crash a grid road northwest of Kinistino, Sask.

A 19-year-old man was ejected from a pickup truck when it rolled on a grid road. STARS air ambulance flew him to Saskatoon with life threatening injuries.

Investigators believe that crash was also alcohol-related.