Speed and alcohol are not being considered as factors in a deadly head-on crash in Cloverdale that closed Highway 10 overnight.

The collision, which happened around 11:30 p.m. Sunday night just east of 176 Street, closed the highway in both directions for more than five hours.

RCMP say a brown Toyota Camry driven by a 26-year-old man heading eastbound on the highway collided with another vehicle.

"For some unknown reason the brown Camry crossed out of its lane across traffic and right into this red Civic," Cpl. Scotty Schumann told CTV News.

The impact of the crash forced the red Honda over the curb off the westbound lanes. Both vehicles suffered severe damage and left the road littered with debris.

The driver of the Civic, a 65-year-old Surrey woman, was pronounced dead at the scene.

The other driver, a Delta resident, was taken to hospital under police escort. He sustained relatively minor injuries and remained in hospital Monday morning.

A witness who spoke to CTV News says the young man’s car crossed three lanes of traffic before hitting the Honda.

The roads were dry at the time, and police are now trying to determine the cause of the crash.

"There's wide range of other things it could be, from a medical condition to falling asleep at the wheel or even distraction," said Cpl. Schumann.

"We don't know if there's been a crime that's been committed or not."

Surrey RCMP has assigned its criminal collision investigation team to the case, and investigators will be aided by an RCMP reconstruction team.

With a report from CTV Morning Live’s Nafeesa Karim