DAYTON, Ohio (CBS SF) -- Authorities who responded to reports of an active shooter at Wright-Patterson Air Force Base in Ohio Thursday afternoon later confirmed that no shooter was found, according to officials.
The officials Wright-Patterson Air Force Base Twitter account made several posts starting at about 1:15 p.m. regarding the incident that began at the on-base hospital facility.
Authorities later confirmed that it was an active shooter incident and base personnel had been instructed to shelter in place.
Authorities said an investigation into the incident is under way, but did not provide any details as to whether anyone had been injured or if the active shooter situation was over.
At around 3:30 p.m. local time, the air force base Twitter account posted that there was "no real world shooter incident" and that all personnel were safe.
Wright-Patterson Air Force Base later released a statement that said someone called 911 during a training exercise that included an active shooter scenario at a separate location. The caller thought there was an incident occurring within the base hospital, sending security forces to the scene where they began searching the entire hospital, the statement said.
While trying to get inside a locked door, a security team member shot his firearm to open the door, the statement said.
Wright-Patterson tweeted that emergency units responded to a "reported incident" around 12:40 p.m. An hour later, they said it was a reported active shooter incident and personnel were instructed to shelter in place on the sprawling base.
Video from outside of the hospital showed service members and others standing outside the building later in the afternoon. Some had come out with their hands in the air.
The Bureau of Alcohol, Tobacco, Firearms and Explosives said via Twitter it was among several agencies responding.
Local police directed traffic away from the base, which is Ohio's largest single-site employer with more than 27,000 civilian employees and military personnel. The Ohio State Highway Patrol and local police also had officers at the base.
© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.
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