MENOMONIE, Wis. (AP) -- Toxicology test results show three college students who died in a house fire in Menomonie in April had blood-alcohol levels from two to almost four times the legal limit in Wisconsin.

Dunn County Medical Examiner Chris Kruse says the three University of Wisconsin-Stout students died from carbon monoxide poisoning, and the deaths have been ruled accidental.

Killed were 20-year-old Amanda Rief of Chaska, Minnesota, 21-year-old April Englund of West St. Paul, Minnesota, and 23-year-old Scott Hams of Hayward.

Investigators have said the fire April 5th started in a love seat in the home's living room, and cigarette butts were found in the room.

The medical examiner says authorities can only speculate whether the alcohol made the three unable to rescue themselves.