Shooting at Fort Hood (VIDEO)

Tragedy strikes once again at Fort Hood where a suspect fatally shot three people, wounded 16 others, before taking his own life on Wednesday.

Armed with a .45-caliber handgun, Army Specialist Ivan Lopez, 34, went from one building to the next shooting people at the military base indiscriminately before putting the gun to his own head and pulling the trigger at around 4 p.m. on Wednesday.

Investigators say that last month, Lopez who served in Iraq as a truck driver, but with no direct combat involvement, was fully examined by a psychiatrist.

However, Lopez was not diagnosed with any severe mental ailments nor was there any indication that he was a danger to himself or others, “so the plan (going) forward was just to continue to monitor and treat him as deemed appropriate,” said Army Secretary John McHugh told the Senate Armed Services Committee on Thursday.

In the past, Lopez did receive medication, including Ambien, to treat anxiety, depression and sleep disturbances.

McHugh added that he had a “clean record” and that there were “no major misbehaviors that we’re yet aware of.”

As far as a motive or what prompted Lopez, a Puerto Rico native, to act out violently, authorities have not reached any definitive conclusions.

“We’re going to keep an open mind. … Possible extremist involvement is still being looked at very, very carefully,” noted McHugh.

While details of the event and the circumstances that precipitated it are still unfolding, politicians, lawmakers and gun-control advocacy are weighing in.

“We are going to get to the bottom of exactly what happened,” said President Obama on Wednesday, upon learning of the incident. “We’re heartbroken that something like this might have happened again.”

Fort Hood witnessed a previous shooting in 2009, when former Army psychiatrist Major Nidal Hasan fatally shot 13 people and wounded 32 others during a rampage.

A self-radicalized extremist, Hasan desired to be a martyr for his cause. On Aug. 23, 2013, Hasan was found guilty on all charges and now faces death by lethal injection.

“Our thoughts are with all those at Ft. Hood tonight as another tragedy unfolds among the heroes who have given their utmost for our country,” said Mark Glaze, executive director of Mayors Against Illegal Guns in a press release.

“We don’t know all the details, but days like this remind us that killers with illegal guns murder 33 more people every day across America,” Glaze continued.  “This March marked the first month in 11 years with no military fatalities in Iraq or Afghanistan. And yet we start the spring with military fatalities on our own home front.”

Meanwhile, at least some gun-rights advocates believe that the strict measures requiring one to register a firearm on base prevented victims and others from defending themselves.

“Pretty amazing after two shootings at Ft. Hood, commanding general says he ‘Does not support military carrying on base’ Says cops good enough,” tweeted conservative author Katie Pavlich on Wednesday.

“Should we stop giving soldiers guns?  Oh wait, already did that. Result? Mass shootings in gun free, defenseless military bases,” she said in another tweet directed at Piers Morgan.