Updated

A fire swept through a mobile home early Wednesday near a tiny western Illinois village, killing five people -- four of them children -- and thwarting rescue efforts of a man who escaped with two sons, an investigator said.

The victims of the blaze included an adult woman, and the oldest child killed was 15 years old, Mercer County Coroner Ron McNall said. The ages of the other children and the identities of all of the victims were not immediately released.

"A neighbor said they were having a sleepover, and that's why there were as many children there," McNall told The Associated Press.

The fire was reported around 1 a.m. and happened just outside of Sherrard, a one-time Mercer County coal-mining town 180 miles west of Chicago and just south of the Quad Cities that has 640 residents.

Investigators were sorting through the trailer home's ruins -- first with machinery, then by hand to not disturb the victims' remains -- for clues to what sparked the blaze that raced through the structure, which was reduced to its steel frame.

The dead woman's husband managed to flee the fire, pushing their two sons to safety, McNall said. But the flames swiftly turned more intense, foiling the man's efforts to re-enter the inferno to save any of the others trapped inside.

"The rest of them didn't make it out," McNall said.

That father sustained burns and was flown to an Iowa hospital. His condition and that of the two boys weren't immediately available.

"It's a tragedy. At this time, we express our heartflet sorrow to the families," Village Clerk Theresa Johnson said, choking back tears. In a community so tiny, "this affects everyone."

"It's just horrible," added Jeannene McNall, whose 84-year-old husband has been the coroner for two decades and never dealt with such a death toll.

But it's hardly the first tragedy for the town. Last June, the area gathered at the high school for funeral services for B.J. Luxmore, a 25-year-old Army corporal who was killed in Afghanistan.

Sherrard's heyday was a century ago, when the village's population reached 900 before the coal mine there shuttered in 1918.