A Naples man was seriously injured Sunday night when he failed to stop at a stop sign and ran his car off the road.

Patrick Connolly III, 48, was taken to Central Maine Medical Center by LifeFlight after he crashed his 2003 Chevrolet at the intersection of routes 302 and 11 around 9 p.m. Sunday. He was driving on Route 11 when he ran the stop sign and struck an embankment, according to police.

Speed and alcohol appear to be factors in the crash, according to Capt. Don Goulet of the Cumberland County Sheriff’s Office.

The sheriff’s office is continuing to investigate the crash.