The man behind the worst church massacre in U.S. history lived in Colorado Springs less than three years ago.

The manager of Fountain Creek RV Park on 3023 W. Colorado Ave. has confirmed with 11 News that Devin Kelley lived at the RV park with his wife from June 2014 until the following January.

An official had previously told CNN that when Kelley bought the rifle he would use to slaughter more than 25 people, he listed the Springs as his address.

Kelley reportedly bought the rifle in San Antonio in April 2016, roughly 35 minutes from where he would go on to commit his monstrous crime a year and a half later.

In a news conference Monday morning, investigators also said Kelley had purchased two other weapons in Colorado, but they didn't say exactly where.

What we know

A man law enforcement now say was Kelley stormed the First Baptist Church in Sutherland Springs during the morning service Sunday. Clad in black tactical-style gear and carrying an assault rifle, he opened fire on the roughly four dozen helpless people inside the church.

There was likely "no way" for the congregants to escape, said the Wilson County sheriff.

Twenty-six people were killed and another 20 were injured. A monstrous loss for the tiny, close-knit community of just a few hundred people.

"Now most of our church family is gone," said Sherri Pomeroy, wife of Pastor Frank Pomeroy. The couple was out of state Sunday but lost their 14-year-old daughter.

The massacre appeared to have started outside, according to sister station KENS 5 in San Antonio, who says that two bodies were found outside the church.

A long-time member of the church said she and her daughter were nearly at Sunday's service but decided not to go at the last minute.

“I’ve been going to this church since I was knee-high to a duck. I changed my mind to go to church today, and so did my daughter," said April, who declined to give a last name.

April said she knew of at least one congregant who escaped the slaughter only because she made the fortuitous decision to leave early and clean the kitchen, to prepare for the post-sermon meal.

“He just walked down the center aisle, turned around and my understanding was shooting on his way back out,” said Wilson County Sheriff Joe Tackitt.

Witnesses told KENS 5 that a community member who had heard the commotion grabbed his own rifle and began shooting at the gunman as he left the building. Kelley reportedly dropped his AR-556 rifle and fled the area, the heroic resident in pursuit.

The Associated Press, citing another San Antonio media outlet, says a second man identified as Johnnie Langendorff was driving by the church as the shooting was unfolding. He said the armed resident jumped in his truck and the two sped after Kelley.

Kelley made it to the Wilson/Guadalupe county line before he lost control of his vehicle and crashed. He was pronounced dead at the scene, and Tackitt said Monday he is believed to have shot himself.

Witness accounts

"If it wasn't for [the armed resident], the guy wouldn't have stopped," said Kevin Jordan, who lives less than 50 yards from the church and was changing his oil when he heard gunfire. He told KENS 5 that resident took cover behind a car while shooting at Kelley and fired at Kelley again through Kelley's car window as the gunman drove away.

Jordan told KENS 5 the shooter fired at his home before turning his weapon on the church and narrowly missed his wife and toddler son.

"When he saw me and I ran, he took a pop shot off at my house."

When it was safe to do so, Jordan, who has medical training, ran to the church to see what he could do to help. He told KENS 5 he "can't even describe" seeing people he had known for years reduced to carnage.

Another neighbor across the road from the church, Ryan Albers, told the Associated Press when he heard gunfire he knew it wasn't just "someone hunting."

"It was definitely not just a shotgun ... it was someone using automatic weapon fire."

Tackitt said the community banded together in the immediate aftermath to make every life-saving effort they could. On a balmy November day, other residents brought water and Gatorade to the citizens-turned-first responders. Sutherland Springs is so small, it does not have paid city staff, so volunteers had to do the heavy lifting until medical personnel could reach the town.

The victims

No one was spared inside the building. The shooter aimed his gunfire at the smallest worshippers, the oldest, and all ages in between. Among the dead, a child just 18 months old and a 77-year-old congregant.

"It’s unbelievable to see children, men and women, laying there. Defenseless people,” Tackitt said.

Survivors say Kelley went aisle by aisle looking for people to shoot and deliberately fired at crying infants.

Sherri Pomeroy, flanked by her husband, spoke of their devastation at losing their daughter Annabelle and most of the congregation.

"As much tragedy as that entails for our family, we don't want to overshadow the other lives lost yesterday," said Sherri Pomeroy. "We lost more than Belle yesterday. And one thing that gives me a sliver of encouragement is that Belle was surrounded yesterday by her church family that she loved fiercely and vice versa. Our church was not comprised of members or parishioners. We were a very close family. We ate together, we laughed together, we cried together, and we worshipped together. Now most of our church family is gone. Our building is probably beyond repair. And the few of us who are left behind lost tragically yesterday."

Frank Pomeroy has been pastor of First Baptist Church since the year before Annabelle was born.

A visiting pastor was among the victims, said Tackitt.

One church member told Texas media that his 8 months pregnant cousin was among those killed, as well as three of her children. He was not at the service that day.

Another local man said a good friend lost eight relatives in the attack.

Twenty people were injured. Ten remain hospitalized in critical condition.

One of the deceased died after arriving at the hospital.

The gunman

Kelley was from the general area, having graduated from high school in nearby San Antonio suburb New Braunfels in 2009. But he made Colorado Springs his home as recently as 2015, and when purchasing the assault rifle in 2016 that he'd one day use in the killings, he put the Springs as his address.

Kelley joined the Air Force one year after graduating high school, but his military career would prove short and troubled. He was court-martialed in 2012 for assaulting his then-wife and her child -- who he reportedly beat so badly that he fractured the little boy's skull. He pleaded guilty and was confined for one year. His rank was reduced to E-1 and he was dishonorably discharged in 2014.

This background should have prevented Kelley from ever getting his hands on a gun. The ATF says that per federal law, anyone who has been dishonorably discharged from the military or has been convicted of domestic violence is prohibited from owning or purchasing a firearm. The Air Force confirmed with 11 News that they

and is now reviewing how this could have happened.

CNN, citing an official, says Kelley bought the AR-556 he'd use in the killings at an Academy Sports & Outdoors store in San Antonio in 2016 and wrote Colorado Springs as an address. He reportedly checked the box indicating he didn't have disqualifying criminal history when he made the purchase.

Kelley reportedly bought three other guns, two of which were bought in Colorado and one in Texas. CBS News has learned in December of 2014 a Glock 9MM handgun was purchased by the suspect at Specialty Sports in Colorado Springs. The store is located along East Fountain Boulevard.

Kelley did not have a license to carry, but “did have a noncommissioned unarmed private security license, similar to a security guard," said Texas Public Safety.

During his time in Colorado, Kelley quickly found himself in trouble with the law.

after witnesses said he tackled a husky and punched it.

CBS News says that in 2014, Kelley was on his second marriage. It would be turmoil with this wife -- whose family attended First Baptist Church Sutherland Springs -- that law enforcement believe may have been a factor in Kelley's decision to commit mass murder.

Motive?

Officials said Monday the attack may have been motivated by marital strife.

"There was a domestic situation going on with this family," the regional director with Texas Public Safety said in a news conference Monday morning. "The suspect's mother-in-law attended this church. We know that she had received threatening texts from the shooter."

Tackitt says Kelley's in-laws attended First Baptist Church but were not there on Sunday. Acquaintances have said based on the tone of Kelley's Facebook messages, it seemed like he was going through marital trouble or a breakup.

Tackitt said it's unclear why Kelley chose Nov. 5 as the day of his rampage.

Response

President Donald Trump tweeted his support to the people of Sutherland Springs and said he was monitoring the event from overseas.

As did former President Barack Obama.

Other messages from lawmakers took what has become a predictable bend post-mass shootings: some called for gun control, others left legislative action out.

The San Antonio Spurs held a moment of silence at their home game Sunday night, played 30 minutes from the crime scene. Star Pau Gasol was among those to tweet his support for those impacted.

Sutherland Springs, home to just 400 people, is located about 35 miles southeast of San Antonio.

Watch the Monday morning news conference: