For about two hours on Thursday, a chaotic scene played out on Wright-Patterson Air Force Base after a report of an active shooter at the hospital in Area A.
The incident temporarily closed all gates and drew responses from upwards of 100 local, state and federal law enforcement officers.
Here’s a rundown of what we now know — and what questions still remain unanswered.
Planned exercise was taking place
On Thursday afternoon, about a half mile from the hospital in the Kittyhawk area of Area A, base personnel were conducting a planned installation exercise that involved an active shooter scenario.
The exercise had been published to all base personnel ahead of time. It involved brightly colored, clearly fake weapons and no real or simulated gunfire, base spokesperson Daryl Mayer said.
The scenario was halted when someone reported what, at the time, was believed to be a real active shooter situation at the hospital.
911 call prompted response
At about 12:40 p.m., someone called 911 and told base emergency dispatchers that there was an active shooter at the medical center, which is near Gate 12A.
Base officials said it appears this person believed there was a real threat, but it is unclear if the exercise going on at Kittyhawk had anything to do with the call.
Upon receiving that call, security forces responded to the hospital and began a systematic sweep of the 99,000-square-foot facility.
Officials said they will not release the audio of that initial 911 call until a full investigation of the incident is complete.
At one point during the sweep of the medical facility, a security officer who has not been identified discharged his weapon, reportedly to gain access to a locked door on the first floor.
U.S. Rep. Mike Turner, R-Dayton, called the use of a firearm to breach a door “highly unusual and highly questionable.”
No one was injured, but a woman who said she was inside the locked room posted photos on Facebook that show what appear to be bullet-sized holes in a wall next to a door. That woman said she and other employees felt “real terror.”
Officials have not confirmed how many shots were fired after initially saying just one. How security forces responded during the sweep is part of an investigation being conducted by the U.S. Air Force Office of Special Investigations.
More 911 calls
More people inside the hospital called 911 to report an active shooter after security forces entered the building.
Some of them reported hearing gunfire. A loud noise, possibly a shot being fired by the security officer, can be heard on at least one of those recorded calls.
The calls made on cell phones went to neighboring dispatch agencies including Fairborn and Greene County, prompting the wider response from outside law enforcement.
Some people inside the hospital also called or texted relatives that they were barricaded inside offices. Rumors of a hostage situation were later proven to be unfounded.
All clear given
At about 2:40 officials gave the all-clear and said there had been no “real world” active shooter. Some people were seen being released from the hospital and walking with their hands up in the air.