SEOUL, South Korea (AP) — The U.S. Osan Air Base in South Korea lifted a lockdown Monday that had been ordered as a precaution after someone reported an unscheduled "active shooter drill" at the high school.

Security forces swept the school and its perimeters and found no injuries or suspicious activities, according to a posting on the base's Facebook site. Morgan Nugent, the principal of Osan American High School, said in a Facebook posting that officials decided to err "on the side of safety" and lock the school down after a teacher received what sounded like an automated call saying there was "an active shooter drill taking place." There was no such drill scheduled Monday.


Osan Air Base, located south of Seoul, is the headquarters of U.S. air forces in South Korea, the 7th Air Force. The base is also home to the 7th Air Forces' 51st Fighter Wing. About 7,500 to 8,000 U.S. troops, civilian employees and their family members live and work on base, according to the base's public affairs office.

About 28,500 U.S. troops are stationed in South Korea as a deterrent to North Korea, whose 1950 attack started the Korean War. The presence of the U.S. troops and annual U.S.-South Korean war drills are a continuing point of contention with North Korea, which claims that they are signs of hostility and designs at invading the North.


The US Air Force's Osan Air Base, located south of Seoul, was forced to lock down Monday due to reports of an active high school shooter. Security forces were dispatched to sweep the base, only to find it was a false alarm.
Following reports of shooting, people on the base have been told to remain in their quarters or workplaces until further notice, AP cited Osan spokesman Tech. Sgt. Stacy Foster as saying.
The US base published a statement on its website, saying that “Osan American High School, Middle School and Elementary School are on lockdown here, along with the entire installation following reports of an active shooter in the location of the school.”
The lockdown was lifted at the base after the “all clear” signal was given as a result of the search.