VICTORIA -- Port Alberni RCMP are investigating after a person died following a single-vehicle crash Thursday.

The crash occurred just after 1 a.m. on Highway 4, near the Alberni Valley Chamber of Commerce.

Police say that a moving van was travelling eastbound on the highway when it drove off the road to the south, ultimately striking a fence.

Mounties say the driver of a car that was travelling behind the van called 911 after the crash and immediately went to check on the occupants of the crashed vehicle.

Paramedics later arrived and treated one occupant of the van who was in "obvious medical distress." First responders attempted to resuscitate the person, who later died of the injuries, according to RCMP.

Meanwhile, another occupant of the van was uninjured during the crash, say police.

The highway was closed overnight as police conducted an initial investigation. The roadway has since reopened.

Port Alberni RCMP, specialized traffic services officers and the BC Coroners Service are conducting investigations into the crash.

Anyone with information is asked to call Port Alberni RCMP at 250-723-2424.