Story highlights Unnamed military policewoman was likely patrolling by herself, former MP leader says

General: She engaged Spc. Ivan Lopez before he killed himself

"It was clearly heroic what she did in that moment in time," Lt. Gen. Milley says

In 2009, another policewoman was credited with helping end Maj. Nidal Hasan's rampage

A soldier has committed a deadly mass shooting at Texas' Fort Hood again. And again, a female police officer was involved in bringing the violent rampage to an end.

The military policewoman has not been identified, but by all accounts, she risked her life to ensure the bedlam wrought by Spc. Ivan Lopez came to a close in the second building he entered.

By then, Lopez, whom the Army chief of staff has described as a "very experienced soldier," had taken three lives and wounded 16 people -- all of them Army personnel. Without the officer's courageous actions, Wednesday's casualty count might have been higher.

"It was clearly heroic what she did in that moment in time," said Lt. Gen. Mark Milley, the post's commander. "She did her job, and she did exactly what we'd expect of a United States Army military police."

According to Milley, the melee began about 4 p.m. Lopez first walked into a unit building and opened fire. The 34-year-old Iraq veteran then left, got into a vehicle and continued firing the .45-caliber Smith & Wesson semiautomatic that he had purchased off-base, Milley said.

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Lopez exited the vehicle and walked into a second building, opening fire again, Milley said. It was there he "was engaged by local law enforcement here at Fort Hood."

The MP arrived in the parking lot about four minutes after the first 911 call, and she began to look for the suspect with other law enforcement officers. A short time later, she saw the suspect.

"He was approaching her at about 20 feet. He put his hands up, then reached under his jacket, pulled out the (semiautomatic) and she pulled out her weapon," the lieutenant general said.

"She engaged, and then he put the weapon to his head and he died of a self-inflicted gunshot wound," Milley said.

The shooting spree was over in about 15 or 20 minutes. The investigation into what spurred Lopez's violent revolt promises to take much longer.

U.S. Rep. John Carter joined Milley in praising the military policewoman in a CNN interview Thursday, saying she "responded exactly as the military would expect." He further said that her quick reaction was a result of training that military police took after the 2009 Fort Hood shooting, in which Maj. Nidal Hasan killed 13 people and wounded 31 others on the base.

"That's the active shooter program they've all been through," Carter said. "We can see that this is the training that was the result of the Hasan shooting. I lived through the Hasan shooting, and it was kind of eerie last night."

In 2009, Sgt. Kimberly Munley , a civilian police officer, was washing her car and topping off the gas tank when she got the report that shots had been fired at Fort Hood. She and Senior Sgt. Mark Todd responded to the scene and were directed to the Soldier Readiness Processing Center.

The 5-foot-2, 125-pound mother of two and her partner exchanged gunfire with Hasan, who shot Munley three times , sending a bullet into each of her thighs and another into her knuckles.

Munley and Todd were credited with ending Hasan's rampage and hailed as heroes. Munley can no longer work in law enforcement because of her injuries and has spoken out on behalf of the victims, whom she claims the government has "betrayed" by denying them certain treatment and benefits in the aftermath of the shooting.

Though not much is yet known about the policewoman involved in ending Wednesday's shooting spree, Fort Hood is home to the 89th Military Police Brigade , a "combat-ready, deployable force" that can support worldwide operations, according to the brigade's web page.

Phillip Carter, a former MP captain on the post, said he believes she was a junior enlisted soldier who was patrolling by herself. He credited her for facing the threat.

"Most police officers probably would have stepped back and waited for backup, but she stepped forward," he said.

Carter told CNN her training would have been 18 weeks and included a "Shoot/No Shoot," class on a shooting course.

"You have to make a decision on the range as to whether to engage or not," he said. "They're designed to create that split-second impulse because that's all you would have in this kind of a situation."