Calgary police say four people are dead after a crash on Stoney Trail late Sunday night.

Officers were called to Stoney Trail just north of 90th Avenue S.W. around 11 p.m.

• Police are set to give an update at 12:45 p.m. Watch that live here

Police said a 30-year-old man in a 2011 Mercedes Benz C350 was driving south in the northbound lanes.

His vehicle struck an oncoming 2016 Subaru Impreza being operated by a 43-year-old man, police said.

“Following the impact, both vehicles caught fire. A Chevrolet Equinox operated by a 52-year-old woman then struck the Mercedes Benz,” police wrote.

As a result of the collision, the occupants of the Mercedes — the driver and passengers, a woman and a child — were pronounced deceased at the scene, police said.

The driver of the Subaru, who police said was the sole occupant of that vehicle, was also pronounced deceased at the scene.

“The driver and three youth passengers of the Chevrolet were transported to hospital, one suffering from life-altering, non-life-threatening injuries,” police said.

The Calgary Fire Department also responded to the scene.

In a release, the department wrote that “firefighters encountered two of the three vehicles fully engulfed in flames.”

“Crews immediately initiated an aggressive fire attack while simultaneously conducting rapid searches of the involved vehicles and providing emergency care to those who could be reached,” the release reads.

Police said impairment and excessive speed on behalf of the driver of the Mercedes Benz are being investigated as factors.

The investigation remains ongoing.