SAN ANTONIO, Texas – An airman shot his commander in an apparent murder-suicide Friday at a U.S. Air Force base in San Antonio, a senior U.S. official said.

The official spoke on condition of anonymity because he wasn't authorized to publicly discuss the shooting at Joint Base San Antonio-Lackland.

Two handguns were found near the bodies of Lieutenant Colonel William A. Schroeder and Technical Sergeant Steven Douglas Bellino, which were inside a building that's used for classrooms and offices, according to Brig. Gen. Robert LaBrutta, who oversees Joint Base San Antonio.

He stressed that the shooting was not an act of terrorism, and declined to identify the two, saying their families must be notified first. The Air Force's Office of Special Investigations is leading the investigation, and the FBI is assisting.

“I just get a text message from her saying active shooter,” said Takari Johnson.

Johnson and his family live on Lackland Air Force Base and his wife is an airman.

“I panicked. I tried calling her and couldn't get a hold of her. I tried texting her, couldn't get a hold of her,” said Johnson.

Lt. Col. Bobby Ford said officials began tactically entering the facility and searching for any active shooter based on the active shooter call.

"Within 8 minutes, they located two potential victims on the first floor," Ford said.

Authorities put the Air Force Base and nearby schools on lock down.

“It was terrifying,” said Rachel Rodriguez.

Rodriguez was visiting her son's school Friday morning.

“The intercom just came on and said, 'lock down, lock down,' so all the teachers and the vice principals in there just and got all the students and told the parents to get up against the walls, away from the doors and windows.”

The fatal shooting of the two is the latest to occur at a military facility in Texas in the last several years.

In January 2015, an Army veteran and former clerk at the veterans' clinic at Fort Bliss in El Paso shot and killed a psychologist, then killed himself. About a year earlier, three soldiers were killed and 16 wounded in an attack at Fort Hood near Killeen by Army Spc. Ivan A. Lopez, who also killed himself.

And in the deadliest attack to occur at a U.S. military installation, 13 people were killed and 31 were wounded in a mass shooting in 2009 at Fort Hood. Nidal Hasan, a former U.S. Army major, was convicted and sentenced to death in that shooting.

Joint Base San Antonio-Lackland is the home of Air Force basic training. The Army's Fort Sam Houston and Air Force's Lackland and Randolph bases were combined during base realignment several years ago to become the military's largest joint base.

“As you all can very well understand our hearts and prayers go out to the families who are going to be affected by this tragedy,” said Brigadier General Robert Labrutta “The care of those families is really the foremost in our minds right now.”