Five people have died and nearly three dozen have been injured after a bus in the US state of Virginia struck six vehicles, police say.

Friday's early morning crash occurred on the southbound side of Interstate 95 as traffic slowed for a work zone, Virginia State Police said.

At least 34 people were taken to hospital, with three in critical condition, police said in a statement. The five who died were in vehicles hit by the bus.

Police are still investigating the multi-vehicle crash. Their early investigation indicates that the bus "failed to slow for traffic" and struck the six vehicles ahead of the work zone. It was not immediately known what the bus had been hired for or who was on board.

Charges in the case are pending, according to the press statement.

Police said the fatal crash occurred at about 0235 local time (0735 BST) on Friday at the 146-mile marker in Stafford County. Southbound lanes were closed for seven hours after the crash while traffic was detoured.

The roadway has since fully reopened, Virginia State Police spokesman Matthew Demlein told the BBC.

In images provided by Virginia State Police, the damaged bus was seen lying in a grassy area alongside the motorway.

The BBC's US media partner CBS News reported that 19 people were taken to Mary Washington Hospital in nearby Fredericksburg. Five of them have been discharged and two remain in critical condition.

Twelve patients were taken to Stafford Hospital and have since been discharged, CBS reported.

A police spokesperson told a local affiliate that there have been two additional crashes in the vicinity of the original crash location.

Demlein declined to comment on that report.