Officials have identified Wednesday’s alleged Fort Hood shooter as 34-year-old Army Spc. Ivan Lopez. Secretary of the Army John McHugh provided more details on Capitol Hill.

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Lopez opened fire wearing his uniform at the Texas military post around 4 p.m. local time. Eye witnesses report hearing at least 20 gunshots. He injured 16, killed three people and then killed himself.

“I know, as we have in the past, we’ll come out the other side of this tempest. Poorer for the losses, but stronger through our resolve,” McHugh said.

Lopez had spent nine years in the Puerto Rico National Guard. He joined the United States Army in June 2008, according to McHugh, and had one four-month deployment to Iraq in 2011. As a truck driver, his records show no physical injuries or direct involvement in combat.

Military leaders say Lopez was recently transferred to Fort Hood in February. He was living in an off-post apartment with his wife and family. He was being treated for anxiety and depression, and had a “self-reported brain injury.”

Lt. General Mark A. Milley told reporters last night, “He was currently under diagnosis for PTSD, but he had not yet been diagnosed.”

Lopez was prescribed medication to address those issues, including Ambien. He was examined last month by a psychiatrist, but there was no sign of likely violence.

He used a .45 caliber Smith & Wesson semi-automatic weapon that he recently purchased. McHugh said soldiers cannot be legally compelled to register their weapons when they live off post. 

Fox News reported Casey Stegall reported that nine victims are being treated at Scott and White Memorial Hospital in Temple, Texas.

Three remain in critical condition and six are listed in stable condition.

Dr. Matt Davis said in a press conference, “I can speak for everyone – I feel invested in the community with the soldiers we have across the way at Fort Hood. […] And I think that anytime they hurt, we hurt.”

Hear audio from the police scanner in the clip above, and watch Army Secretary McHugh's remarks below.