The Boulder County Coroner’s Office has identified one of two men killed in a two-vehicle crash at U.S. 287 and Plateau Road in Longmont as Allen Leszczynski, of Aurora.

Leszczynski, 46, died at Boulder Community Health, according to a news release.

Leszczynski was driving a green Subaru Outback northbound on U.S. 287 shortly after noon when he crossed into the southbound lane and struck a green Honda Accord, according to the Colorado State Patrol.

State Trooper Alisha Danko said that the next of kin of the man driving the Accord has not been notified. She said he was a Colorado man but did not release any further information.

Danko said that the two vehicles collided on the drivers’ sides and spun around, and the Accord struck a guard rail. The driver of the Accord died at the scene.

Leszczynski was airlifted to Boulder Community Health’s Foothills Hospital where he later died. There were no passengers in either vehicle.

Police shut down southbound U.S. 287 until 3:30 p.m., and the road was closed in both directions until about 1:30 p.m.

The state patrol is investigating the cause of the crash. Speed does not appear to be a factor but marijuana is being investigated as a possible contributing factor.

Amelia Arvesen: 303-684-5212, arvesena@times-call.com or twitter.com/ameliaarvesen

John Bear: 303-473-1355, bearj@dailycamera.com or twitter.com/johnbearwithme