Police are searching for a 21-year-old University of Wisconsin-La Crosse student who went missing Friday night.

Sgt. Jim Ballas of the La Crosse Police Department said Luke Homan was out celebrating La Crosse's annual Oktoberfest U.S.A. when he disappeared.

"The case is still under investigation," Ballas told The Badger Herald. "We have detectives working on it."

Ballas added that extra volunteers have helped look for Homan, as police spent much of Sunday searching for the missing student throughout the city of La Crosse and in the Mississippi River.

UW-La Crosse Director of University Relations Cary Heyer said Sunday that more than 100 volunteers, particularly student athletes and Homan's basketball teammates, are participating in the search.

"Everyone is doing everything they can to help out in a small way," Heyer said, specifically pointing to residents' efforts in hanging posters up throughout the city. "They'll know a lot more [Monday]."

Heyer added that, while it's not necessarily the focus of the search, there is an "intensive search in the [Mississippi] River."

Because Homan is believed to have gone missing off-campus, Heyer said La Crosse Police, not UW-La Crosse Police, are in charge of the investigation.

Homan plays on the UW-La Crosse basketball team, Heyer said, and is a native of Brookfield and a graduate of Brookfield Central High School.

Ballas added that Homan's family has traveled to La Crosse from their home town, as they are helping in the search for their son.

Since 1997, eight students have drowned in the Mississippi River near La Crosse, and alcohol was involved in each case.

In January, Cullen Fortney, a UW-Madison student, fell in the river after a night of drinking with two friends. Fortney managed to survive by pulling himself up to safety.

Homan had attended Oktoberfest U.S.A. the evening he went missing; Oktoberfest is an annual celebration of German heritage that lasts through Tuesday.