A mother and her three children died Saturday morning in a fire that engulfed their trailer home along the Kenai Spur Highway, according to local firefighters.

The husband and father, Frank Hunt, 26, of Kenai, escaped the flames by jumping out a window, said Mike Tilly, chief of the Kenai Fire Department.

Firefighters, local police, the Alaska fire marshal and the state medical examiner are investigating the deaths of Christina Hunt, 31, and her children: Judy Jones, 13; Frankie Hunt, 7; and Ryan Hunt, 4.

Kenai Police Chief Chuck Kopp said he doesn't know yet how the fire started. He said the Kenai dispatch center received a 911 call at 9:55 a.m. from a passing motorist who saw smoke coming from the trailer, next to the highway and near the Beaver Loop Road.

When firefighters and police arrived about seven minutes later, the mobile home was engulfed, with flames shooting out of almost every window, Tilly said.

Hunt was outside the trailer and was not hurt, he said.

Tilly said Hunt told firefighters that he didn't know where or how the fire started. He escaped through a window because the door was blocked.

Prevailing winds helped keep the fire from spreading to two other structures attached to the trailer, Tilly said.

Firefighters extinguished the fire by about 10:40 a.m. but offered no information about the investigation so far.

"Right now, it's not clear how or where the fire started," Tilly said.

The Hunt family has lived at the property for about three years, and another family lives in an adjoining structure, Kopp said.

The father is staying with family members who live in the area, Kopp said.

Autopsies of the victims are planned, Tilly said

"It's very sad, very unfortunate," Kopp said. "We're going to determine what happened so we can better promote fire safety among our residents to prevent a similar situation from occurring."

It's been close to 10 years since anyone has died in a local fire, Tilly said. "We don't have that many fatality fires and we're pretty proud of that," he said.