A report of smoke on the second floor in the Stony Brook Union had students evacuating the building at about 4:30 p.m. on Wednesday.

According to Lauren Sheprow, a Stony Brook University spokeswoman, campus police, Environmental Health & Safety Fire Marshals and the Setauket Fire Department responded to a smoke condition on the second floor.

A fan coil unit, in a concrete enclosure below floor level, for the perimeter heating system burned out and began to emit smoke. The unit was removed for repair.

Hundreds of students crowded around the Union, taking pictures on their iPhones behind the yellow tape and fire trucks. Posts were on Facebook and Tumblr within minutes. Students were allowed back into the Union shortly after.

No injuries or property damages were reported.