Reports of an active shooter in a San Diego naval facility sparked an evacuation and the temporary lockdown of area schools on Tuesday after a witness reported hearing three shots fired.
But officials later said there was no sign of a shooting at the Naval Medical Center San Diego's building 26 and no reports of deaths or injuries.
"There’s no evidence of a shooting right now that we know of, there was just a report of three shots heard," Navy Region Southwest spokeswoman Amanda Chavez said, Reuters reported.
Occupants of the building had earlier been advised to "run, hide or fight" in a startling message posted to the facility's Facebook page.
All non-emergency response personnel were asked to stay away from the compound as footage taken at the facility showed people calmly walking away.
The official Facebook of the base, which tens of thousands of people call home, also posted about the reports on Tuesday:
“If you are in the vicinity, shelter in place. If in immediate danger, hide or seek shelter in secure space. Barricade the door and dial 911. Silence phones and other devices. Stay away from doors and windows. Remain calm and quiet."
Less than two hours into the situation, three area schools that had been on lockdown following reports of a shooting returned to normal.
The base posted to Facebook even before the lockdown was lifted:
"For all concerned, the childcare facilities at NMC are currently secured. All children are accounted for and safe. The entire complex is secured, there is no access to the facilities at this time. We are monitoring this page and will continue to provide updates."
In the wake of reports of the shooting, CNN reported that officials were interviewing the witness who heard what he thought were shots.
The Naval Medical Center San Diego bills itself as "the largest and most comprehensive military healthcare system in the Western United States."
In 2014, the center admitted some 19,000 patients and recorded 1.2 million outpatient visits.