COLLEGE STATION, Texas – Four workers were hurt, three critically, after a barn frame collapsed Saturday at an $80 million Texas A&M University equestrian complex that’s under construction.

The collapse happened on university property about a mile from the main campus, Texas A&M spokesman Lane Stephenson said.

College Station and Bryan fire departments, campus police and Texas A&M emergency medical personnel all responded to the accident, which happened shortly before 11 a.m. Saturday.

The accident involved an approximately 300-foot barn, according to the College Station Fire Department. Twisted metal beams could be seen at the site, where ground was broken last fall.

The injured workers were transported to hospitals. Nobody else was hurt.

For a time, emergency responders had to halt the search for the four because of concerns about another collapse.

Texas A&M police officials were trying to determine what caused the collapse. University police identified the contractor as Gamma Construction Company, with offices in Houston and San Antonio.

Gamma Construction, on its website, described the A&M work as one of its 2013 projects.

The first phase of the equestrian center was set for completion in 2014.

The facility will include locker rooms, offices, a concessions building, a 50-stall barn, plus practice arenas and two covered competition arenas, according to the university.