ANCHORAGE, Alaska (Reuters) - A fire, apparently started by an inmate, engulfed a jail in an Alaska village on Sunday, killing two prisoners and badly injuring a guard, authorities said.

The jail in the remote Yup’ik community of Napakiak went up in flames after a prisoner set fire to a mattress, according to a guard at the jail, the Alaska State Troopers said.

The prisoner and his cellmate were killed, and a guard who tried to free them suffered “significant injuries,” the state troopers said in a news release.

The two bodies were found after the fire was extinguished and will be sent to the state medical examiner’s office in Anchorage for autopsies and identifications, the release said.

Napakiak is home to about 360 people, most of them engaging in a traditional Yup’ik lifestyle. The village is on the Kuskokwim River, about 400 miles (645 km) west of Anchorage. Like most rural Alaska villages, Napakiak lacks outside road access.

The injured guard was flown out of the community for treatment, state troopers said. A state investigator and deputy fire marshals are traveling to Napakiak to investigate.