MENOMONIE, Wis. (AP) - Investigators believe the fire which killed three University of Wisconsin-Stout students at an off-campus duplex Saturday was accidental, the Menomonie police chief said Sunday.

"We believe it was nothing but a horrific and tragic accident," Chief Dennis Beety said, but he declined to discuss further details.

Battalion Fire Chief Denny Klass declined to comment Sunday on what may have ignited the blaze or other details, saying officials are waiting to get a report from the state fire marshal who investigated the matter along with the Menomonie police and fire departments.

Klass said he expected that report to be available soon.

But Beety said toxicology reports being done by the State Crime Lab are not expected to be completed for about a month.

The university has identified the victims as April C. Englund, 21, of West St. Paul, Minn.; Amanda Jean Rief, 20, of Chaska, Minn.; and Scott A. Hams, 23, of Hayward. Each was found on the floor of a different bedroom after neighbors who heard smoke alarms alerted authorities.

All three appeared to have died of smoke inhalation, police Lt. Wendy Stelter said earlier.

Beety had said Saturday that a bottle of alcohol was found with the top off of it, but he said that didn't mean the students were drinking at the house.

Authorities have said Englund was the only victim who lived in the unit, and Rief and Hams were sleeping over because Englund's roommates had left town.

The school of 8,400 students is about 70 miles east of Minneapolis.

Visitation will be held on Wednesday from 4 p.m. to 8 p.m. for Englund. Her visitation will be held at the Johnson-Peterson Funeral Home in St. Paul. Her funeral will be held at First Baptist Church in St. Paul at 11 a.m. on Thursday.

Information on visitation and funeral arrangements for Hams and Rief has not been released.