Witnesses reported that a semi-trailer lost its brakes on the Coquihalla Highway midafternoon Friday, Aug. 5, colliding with multiple vehicles and injuring nine people near Box Canyon.
Traffic on the busy route was backed up for kilometres and there was no indication when the southbound lane might reopen.
Estimates suggested that as few as 10 and as many as 30 vehicles were involved in the accident, believed to have been started by a semi-trailer that lost control around 2:30 p.m.
Initial reports indicated that as many as 40 people were injured, but the number was later reduced to nine.
Witnesses said dozens of vehicles were in the way when the transport truck appeared to lose its brakes.
Hwy. 5 southbound traffic was closed at Box Canyon and travellers were advised to consider using Hwy. 8, Hwy. 97C or taking Exit 286 in Merritt to access Hwy. 5A.
Officers from the Fraser Valley traffic unit and B.C. Ambulance Service paramedics were responding.
Drivers in the northbound lanes could also be affected, police said.
One witness said it appears that the semi-truck lost its brakes and barrelled down the hill in the southbound lanes, colliding with as many as two dozen vehicles.
With files from Castanet