As the military police soldier approached him, Spc. Ivan Lopez-Lopez took a few steps forward.

"You better kill me now," he said. "I was the shooter. Kill me."

Lopez-Lopez then pulled a pistol from inside the waistband of his Army Combat Uniform trousers, charged the weapon, and placed it to the right side of his head.

He fired.

The exchange lasted less than a minute, bringing to an end a deadly shooting spree that killed three soldiers and wounded 12 others at Fort Hood, Texas. It was the second such incident at the Texas installation in five years.

The Army investigation into the April 2, 2014, shooting did not find anything in Lopez-Lopez's background, medical or military profiles that might have provided an early warning for potential violence, according to findings released Friday.

But the investigation noted that Lopez-Lopez had recently experienced the deaths of his grandfather and mother, was facing at least $14,000 in delinquent debts, had been counseled about non-promotion, and was being treated for behavioral health conditions ranging from depression and anxiety to sleep disturbance.

He also had only recently arrived at Fort Hood from a previous assignment, the Army said, and evidence shows the married Lopez-Lopez maintained a Facebook persona under the name "Anthony Drako" that he apparently used to meet and carry on relationships with several women.

Simultaneously, Lopez-Lopez's unit was experiencing "significant turnover in leadership" and struggling with "high operational tempo and manning shortages," which led to possible breakdowns in communication and leaders being "unable to provide adequate time to train, mentor and lead," according to the Army.

This photo provided by Glidden Lopez shows Army Spc. Ivan Lopez. Lopez killed three people and wounded 16 others in a shooting at Fort Hood, Texas, on Wednesday, April 2, 2014, before killing himself. Investigators believe his unstable mental health contributed to the rampage. (AP Photo/Courtesy of Glidden Lopez)
This photo provided by Glidden Lopez shows Army Spc. Ivan Lopez. Lopez killed three people and wounded 16 others in a shooting at Fort Hood, Texas, on Wednesday, April 2, 2014, before killing himself. Investigators believe his unstable mental health contributed to the rampage. (AP Photo/Courtesy of Glidden Lopez)

The investigation found that Spc. Ivan Lopez-Lopez was being treated for a variety of medical conditions.

Photo Credit: (AP Photo/Courtesy of Glidden Lopez)

Lopez-Lopez, 34, opened fire April 2, 2014, after an argument in the personnel section. He then left and drove away, shooting at times from his car. Three soldiers were killed, gunned down in separate locations. Twelve others were wounded.

Lopez-Lopez killed himself after he was confronted by a military police officer.

Killed that day were Sgt. 1st Class Danny Ferguson, Sgt. Timothy Owens and Staff Sgt. Carlos Lazaney-Rodriguez.

Ferguson, who had just returned from Afghanistan at the time of the shooting, died while trying to hold shut a door that would have led the gunman to a room packed with military personnel.

Ferguson, a transportation management specialist, joined the Army in 1993. He had deployed four times since 2003.

Owens, who was shot in the chest, was an Iraq war veteran.

Lazaney-Rodriguez joined the Army in 1994, deploying to Iraq twice and once to Kuwait.

"All of us here at Fort Hood remain deeply saddened by the tragedy that took place here April 2, 2014," said Col. Christopher Garver, spokesman for III Corps, in a statement. "Our leaders continue to work with those who were affected by this tragedy, and we extend our continued condolences to those who lost loved ones and to those who suffered wounds."

The Army's investigation included several recommendations, Garver said.

"The Army, including Fort Hood, is currently in the process of evaluating and implementing those recommendations," he said. "Some recommendations work to improve information flow in units, between Army medical facilities and between leadership and their soldiers, and others deal with safety and security measures. Since the incident on April 2, Fort Hood has continued to improve these measures."

During the Army's months-long investigation into the shooting, an investigation team interviewed and obtained sworn statements from 169 witnesses. The team also reviewed materials and statements gathered during an earlier criminal investigation.

"We find no indication in his medical and personnel records suggesting Spc. Lopez-Lopez was likely to commit a violent act," Lt. Gen. Joseph Martz, who led the investigation, wrote in the report.

The investigation also determined that no "single event or stressor, in isolation, was the cause of the shooting," and "there were no clear warning signs," according to the Army.

However, a substantive review of Lopez-Lopez's background found several factors that may have contributed to the soldier's state of mind, including his money troubles and the deaths of his mother and grandfather, the Army said.

Lopez-Lopez had almost 15 years of service, serving in the Puerto Rico National Guard as an infantryman, including a 12-month deployment to the Sinai in 2007, before going on active duty in 2010.

While on active duty, Lopez-Lopez deployed to Iraq in support of Operation New Dawn from August through December 2011 with 4th Brigade Combat Team, 1st Armored Division, of Fort Bliss, Texas.

In the months after coming home, Lopez-Lopez was counseled for non-promotion, according to the report. He later became a team leader but was subsequently moved because one of the squad's privates first class was viewed as more qualified, according to the report.

He later received a permanent profile and received permission to reclass to 88M, or motor transport operator. During this time, the frequency of his medical appointments increased, the report states.

In October 2013, Lopez-Lopez's grandfather passed away. His mother died unexpectedly just one month later.

When Lopez-Lopez returned from his mother's funeral, he reported to 88M advanced individual training at Fort Leonard Wood, Missouri. He arrived at Fort Hood in February 2014 and was assigned to the 154th Transportation Company, which is part of the 13th Sustainment Command.

According to the report, Lopez-Lopez requested permissive temporary duty almost immediately after reporting to his company, telling him chain of command he needed the time off to get his family.

He was told he had to wait 14 days to fully in-process into the unit. In the meantime, his acting first sergeant gave him a four-day pass, which he used to pick up his wife and daughter in Odessa, Texas, on his way to Fort Bliss to get his personal belongings.

Lopez-Lopez returned to work on March 31, 2014, the same day his PTDY request form was returned with errors. He made the corrections and submitted it again. His company commander than hand-carried the leave form to the battalion commander, who signed it April 1. However, the form didn't have a control number, which led to rising tensions on April 2, according to the investigation.

On April 2, after physical training and the morning accountability formation, Lopez-Lopez was told to go sign out for his 10 days of PTDY at the 49th Transportation Battalion headquarters.

But he soon ran into issues, first with the paperwork and then with whether he was eligible for PTDY because he had already established his household at Fort Hood. The back and forth went on all day, with Lopez-Lopez leaving and returning to the battalion headquarters multiple times.

At one point, he went home to his off-post apartment and got his Smith & Wesson .45 caliber pistol, telling his wife he was going shooting after work.

When Lopez-Lopez returned to the battalion headquarters, he got into an argument with someone there.

At 4:15 p.m., Lopez-Lopez walked up to the open door to the office, aimed his weapon and began shooting, the report states.

He then moved toward the conference room and tried to go inside, but Ferguson and others barricaded the door.

Lopez-Lopez fired several rounds through the door, fatally wounding Ferguson.

He then left the building, got into his car and drove west toward 73rd Street. As he drove north on 73rd Street, Lopez-Lopez saw someone standing beside the road. He stopped, rolled down his window and fired three rounds.

The victim's name is redacted in the report.

Lopez-Lopez drove on, eventually parking his car outside the fence of the 154th Transportation Company's motor pool.

He walked through the gate, entered the building and into the office in the southeast corner, and opened fire, fatally wounding Owens.

Lopez-Lopez returned to his car and drove east on Motorpool Road, firing his weapon at least twice along the way.

He ended up in the parking lot of the 1st Medical Brigade headquarters and walked into a nearby building, firing at three soldiers in the staff duty office. Lazaney-Rodriguez was killed and two other soldiers were wounded.

Lopez-Lopez then got back into his car one more time and drove to a parking lot just north of the 49th Transportation headquarters.

At 4:25 p.m., Lopez-Lopez got out of his car and was confronted by a military police soldier.

He would be dead seconds later.

In the course of its investigation, the Army determined that Lopez-Lopez's chain of command, which was stretched thin and coping with a high op-tempo, would have had difficulty recognizing personal problems or providing help that may have been needed.

"Since risk assessment tools depend on self-reporting, they are subject to the soldier's willingness to identify risk factors accurately," the report states.

The report also noted that Lopez-Lopez could sometimes be "misleading or deceptive."

At the end of his unit's Iraq deployment in 2011, Lopez-Lopez was in a convoy that was hit by an improvised explosive device. Although Lopez-Lopez later claimed to be near an explosion, there is no evidence he was within the blast radius of the IED, the report states.

The report also cited Lopez-Lopez's "Anthony Drako" Facebook profile, which was "not known to many of his friends and family members."

On the profile, he claimed to be an Army sniper who had traveled to the Central African Republic, among other places, according to the report. He also used that persona to meet women, one of whom claimed on her Facebook page to be married to Lopez-Lopez.

Lopez-Lopez also was found to have lied about his marital status to Army officials at Fort Leonard Wood and neglecting to mention his wife and daughter were living with her mother in Odessa, Texas, when he requested permissive temporary duty, according to the report. Instead, he implied to his superiors at Fort Hood that his family was still in El Paso, Texas, with his household goods.

Lopez-Lopez also told family and acquaintances in Puerto Rico that he was given less than 48 hours leave to attend his mother's funeral, the report states. Records show he was off for six days, according to the report.

Investigators also believe that there were indications that Lopez-Lopez may have been faking some of his health problems to try and "build justifications to receive VA disability," the report states.

"In the absence of a system capable of identifying Lopez-Lopez as a threat, and because the unit was unaware and unable to address the variety of stressors in Lopez-Lopez's life, Fort Hood was not able to prevent the shooting," Martz wrote.

The report includes several recommendations to improve unit leaders' interaction with new soldiers.

It also recommends examining whether soldiers should be required to register personally-owned weapons with their command.

Lopez-Lopez bought two weapons without the knowledge of his leadership. One was stolen just weeks before the shooting, and the other was used in the April shooting.

"This impacts a commander's ability to maintain situational awareness over a service member and their actions involving a firearm that could be concealed and brought onto the installation for unauthorized purposes," the report states.

The shooting was the second such incident on Fort Hood in recent years. In 2009, 13 people were killed by then-Maj. Nidal Hasan, who has said he was angry about being deployed to Afghanistan and wanted to protect Islamic and Taliban leaders from U.S. troops.