A bus crashed into six cars on Interstate 95 in Virginia early Friday morning, killing five people and injuring nearly three dozen others, the state police said.

The bus was in a southbound lane when its driver failed to slow for traffic as it approached a work zone near Quantico, Va., and it plowed into six vehicles around 2:35 a.m., the police said in a news release. All five people who died were in vehicles hit by the bus; 34 others were injured, three of them critically, the police said.

Authorities did not say where the bus was going or how many people were onboard. The highway’s southbound lanes were closed for seven hours after the crash and began to reopen around 9:30 a.m., the Virginia Department of Transportation said on social media, but delays were ongoing.

The crash is under investigation and the police said charges were pending.

The bus was operated by E & P Travel Inc. of Kings Mountain, N.C., a representative of the company, who declined to give her name, said on Friday when reached by phone.

She said the bus line normally operates between New York and Charlotte, N.C.

This is a developing story.