BANGOR, Maine — A Southwest Harbor man pleaded guilty Monday in federal court to several charges, including operating under the influence and causing serious bodily injury, for his role in a motor vehicle crash two years ago in Acadia National Park.

Justin S. Bent, 28, was drunk May 14, 2014, when he drove a 2002 Dodge Caravan off Seal Cove Road in the park and crashed into some trees, causing serious injury to a passenger, according to court records. The passenger was flown to Eastern Maine Medical Center in Bangor, where he underwent emergency surgery for a severe leg fracture, Assistant U.S. Attorney Jim Moore reported in a news release issued Tuesday.

The prosecutor said Bent’s blood alcohol content was .14, nearly twice the .08 legal limit for driving a vehicle in Maine.

Earlier charges against Bent were misdemeanors, but after federal prosecutors learned the passenger’s injuries were more severe than initially reported, they filed a new charge earlier this month — operating a motor vehicle under the influence of intoxicants and causing serious bodily injury — which is a felony.

Last October, the U.S. attorney’s office learned the passenger was paid $97,000 as a result of a settlement in a civil lawsuit he had filed against Bent, court documents indicate.

“A substantial amount of the settlement sum was paid for reimbursement of medical bills,” federal prosecutors wrote in a filing in January that included a supplemental report by park rangers who investigated the accident with local police.

The passenger has a titanium rod in his right leg, a scar about a foot long and walks with a limp, according to the court documents. He told park rangers in December 2015 that he had three months of physical therapy, suffers from chronic pain and had to quit his job as a caretaker at an inn in Southwest Harbor. Additional surgery may be required, park rangers wrote in the supplemental report.

Bent pleaded guilty Monday in U.S. District Court to operating under the influence and causing serious bodily injury; operating a vehicle without due care; and destroying trees and other natural resources.

He faces up to six years in prison and a $250,000 fine for the felony OUI causing injury and up to six months for the lesser violations, according to the release from the U.S. Attorney’s Office.

He will be sentenced after the U.S. Probation Office completes a presentence investigation report.