John F. Kennedy High School sheltered in place for more than 20 minutes Wednesday following a report of an alleged weapon on campus that police later identified as an airsoft gun, according to the Guam Department of Education and Guam Police Department.

GPD said a student reported seeing another student brandishing what appeared to be a firearm. The report prompted the school to initiate shelter-in-place procedures and notify authorities at 12:09 a.m., GDOE said.

Police located the student and found an airsoft gun, GPD said. Officers then issued the all-clear.

The school returned to normal operations at 12:32 p.m., according to GDOE.