Police are investigating a head-on collision on Beach Road in Oak Bluffs that caused major traffic diversions but no injuries.

Oak Bluffs police Lt. Timothy Williamson said a Chevy sedan crossed the center line and hit a taxi van head-on in front of the restaurant Hooked. The crash occurred around 1 p.m. The taxi was not carrying passengers.

Lt. Williamson said police are investigating whether the driver of the sedan “may have been impaired.”

“The early indication is that it looks like the operator crossed the center line into oncoming traffic,” he said.

Lt. Williamson said police are also looking into whether the driver of the sedan sideswiped a car in the Cow Bay area of Beach Road in Edgartown.

Beach Road was closed from the Triangle in Edgartown to Oak Bluffs in order to clear debris, Lt. Williamson said. Edgartown police chief Antone Bettencourt diverted the bumper-to-bumper July 4 traffic to Edgartown-Vineyard Haven Road.

The road remained closed for about an hour; it has since been reopened.