Five children were killed and several others were injured in a two-vehicle collision in rural Ontario, according to the Ontario Provincial Police.

The OPP say the crash happened around 7:30 p.m., Friday evening, in Mapleton Township, at the intersection of 4th Line and Wellington Road 12. That’s about 35 km northwest of Kitchener-Waterloo.

A total of 11 people were involved in the collision, Dwight Thib, commander for the OPP West Region, said in a news conference Saturday.

Ten people in a passenger van and one person in a sport utility vehicle collided at the intersection, said Thib.

In the crash, four girls and one boy died, Thib said. The children were four, six, eight, ten and 12 years old, according to the OPP. They were all related.

“This is an unimaginable loss,” Thib said. “On behalf of the Ontario Provincial Police, I extend our deepest condolences to the families, loved ones and the community during this incredibly difficult time.”

Thib said an infant and four adults in the van were seriously injured, along with the the driver of the SUV. They are all in hospital.

The OPP Traffic Incident Management Enforcement team has been called in, and the traffic will be rerouted around the area while the investigation continues.

The intersection will be closed for most of Saturday, officers added.

Police said they are not releasing further details as the investigation is ongoing.