Activated charcoal was the cause of a fire alarm today in the Chemistry and Natural Sciences Building at the University of Louisiana at Monroe, according to the Monroe Fire Department.

Responding to a call from the University Police Department, firefighters checked the scene but found no fire or chemical spill. There were no injuries and the building was re-opened at about 11:25 a.m.

Activated charcoal is used to treat patients who have poisonings and overdoses.

UPD, Monroe Police and the Fire Department kept students back as the situation was investigated.

“[It was] chaotic,” junior biology major Stormy Knight said. “They didn’t tell us what it was, they just made us leave, but everybody was in a rush. The teachers were really worried because it was an unknown chemical.”

ULM Interim President Stephen Richters said in a statement: “On behalf of the university, I would like to express my appreciation to the Monroe City Fire Department and the ULM Police Department for their professional and timely response. Their rapid reaction to this incident demonstrates that the city and university emergency protocols are firmly in place, ensuring the safety of our university family should a serious incident ever occur.”