Sirens sounded at Fort Hood giving the all clear as lockdown was lifted hours after the deadly shooting.
Just before 5 p.m. Wednesday, a gunman opened fire at Fort Hood in an attack that left 4 dead, including the gunman and injured 16.
The shooting happened less than an hour before the recording of retreat and colors played to signal the end of the day.
Instead of hearing a bugle play everyone on post heard a safety alert message blare out.
The shooting set off a massive response by emergency crews on post and from the surrounding communities. The gates were locked down and everyone on post went into what's called shelter in place.
According to Lt. Gen. Mark Milley, a male soldier wearing his army uniform fired shots in the First Medical Brigade area, killing three people and injuring 16 others. He then turned the gun, .45 caliber semi-automatic pistol, a on himself as he was approached by a female officer.
The soldier, who transferred to Fort Hood from another installation in February, served four months in Iraq in 2011, and was under diagnoses for PTSD, according to Milley. He says the soldier is married and has a family. His name is not being released at this time pending notification of his family.
A total of six victims were transported to Scott and White, a level 1 trauma center in Temple after being treated at the Darnall Army Medical Center emergency facilities. The first four victims admitted had gunshot wounds to the chest, abdomen, extremities, and to the neck and their conditions range from stable to "quite critical." The last 2 patients to arrive will be going directly into operating rooms because of the severity of their injuries.
The other victims are being treated at Darnall Army Medical Center.
According to Milley, all victims are members of the military, no civilians were involved.
This isn't the first shooting reported at Fort Hood. On November 5, 2009, former army psychiatrist Nidal Hasan gunned down dozens at the army post. He killed 13 people and injured more than 30.
In August 2013, a military tribunal convicted Hasan of those crimes and sentenced him to death.
Hasan admitted to the shooting, and said the attack was a Jihad against the U.S. wars in Iraq and Afghanistan.
"My concern is that Ft. Hood is sort of becoming a target for potential Jihadists," McCaul said during a press conference Wednesday night. "At this point and time we have no information on the motivation behind this. The Joint Terrorism Task Force is running down information as I speak on the individual who was killed.
According to Milley, there is no indication the shooting is related to terrorism, but it is not being ruled out.