NORTHPORT, Maine — Six people were taken to the hospital, three with serious injuries, after a three-car crash Monday morning on U.S. Route 1.

The accident caused police to close a portion of the busy coastal highway for about four hours while the crash was being investigated and reconstructed. First responders found that the road was totally blocked by the three vehicles and six injured people involved in the collision.

Police said the chain-reaction accident occurred at 11:24 a.m. when Everett Hall, 44, of Swanville, who had stopped to make a left-hand turn, was rear-ended by a truck.

The force of the impact with the truck, a 2003 Dodge Dakota driven by Ralph Harriman, 59, of Searsport, sent Hall’s 2005 Ford Explorer into the northbound lane of traffic.

That’s where it collided head-on with William Goldenstein, 71, of Toronto, who was driving a 2005 Porsche SUV with his wife, Evelyn Goldenstein, 68, traveling as his passenger, according to a press release from the Waldo County Sheriff’s Department.

William Goldenstein initially was taken to Waldo County General Hospital by ambulance and later was transported by LifeFlight ambulance to Eastern Maine Medical Center in Bangor for treatment of serious injuries.

A hospital spokesperson said at 5 p.m. that he still was listed in serious condition.

Evelyn Goldenstein was taken to Waldo County General Hospital in Belfast, where she was treated and then released, according to the police report.

Hall and two minors who were passengers in his vehicle initially were taken to Waldo County General Hospital in an ambulance. Police did not provide the names of the minors. One youth was treated there and released, and Hall and the other minor passenger were taken to Eastern Maine Medical Center with serious injuries.

The EMMC spokesperson said that Hall continued to be listed in serious condition. No information was available on the youth.

Harriman was taken to the Belfast hospital where he was treated for his injuries and and then released.

Detective Matt Curtis of the sheriff’s office is the primary investigator, with assistance from Lt. Jason Trundy and Deputy Darrin Moody.

Sgt. Ken Smith of the Rockland Police Department is reconstructing the crash and Maine State Police Sgt. Darren Foster did the forensic mapping of the crash.

Northport First Responders, Northport Fire Department, Belfast Fire Department, Belfast Ambulance and Searsport Ambulance all assisted at the scene, according to the police press release.