Police respond to a fatal multi-vehicle crash on Hwy. 401 in Dutton, August 29, 2017. (Photo courtesy of the OPP)

UPDATE: OPP Identify Fatal Hwy. 401 Crash Victims

Elgin OPP are investigating after a collision that has claimed the lives of a mother and her child.

Police say 42-year-old Sarah Payne and 5-year-old Freya Payne, both from London, were killed when the grey Honda van they were in was hit by a grey Ford pickup truck that had crossed over the median and into oncoming traffic.

The OPP first reported the collision near Dutton on Tuesday around 4:40pm.

Officers say a 6-year-old boy, identified as William Payne from London, was also in the van at the time of the crash and is now in stable condition.

The 56-year-old man from Cambridge who was driving the pickup truck is also said to be in stable condition.

The highway was closed between Currie Rd. and Iona Rd. while police conducted an investigation. All lanes were reopened around 11:30pm.

-With files from Matt Weverink

Traffic backed up on Hwy. 401 in Dutton following a multi-vehicle crash, August 29, 2017. (Photo courtesy of the OPP)

Traffic backed up on Hwy. 401 in Dutton following a multi-vehicle crash, August 29, 2017. (Photo courtesy of the OPP)