The University of Michigan says there is no active threat after it warned of an active shooter situation on its main campus late Saturday afternoon.

The university sent out

at 4:36 p.m. that said an active shooter was in Mason Hall, an academic building that houses part of UM's College of Literature, Science and the Arts.

The alert urged people in the area to "run, hide, fight," the university's

.

About an hour later the university sent out an alert saying, "There does not appear to be an active threat to the community."

The Washtenaw County Sheriff's Office told News 10 just after 5:30 p.m. that its assistance had been called off. Campus police, though, continue to investigate. The university urges people to still stay clear of the Mason Hall area.

Detroit NBC affiliate WDIV

that the active shooter situation was a false alarm caused by teenagers popping balloons near Mason Hall.