NEW BRAUNFELS, TEXAS (WASHINGTON POST) - Authorities worked on multiple fronts seeking a fuller portrait of the gunman who left at least 26 people dead at a Texas church and how a breakdown in military protocols failed to flag a domestic violence conviction that should have kept him from buying firearms.

Even as tiny Sutherland Springs, Texas, began funerals and mourning that touch nearly every family, more chilling details emerged of how the black-clad attacker, Devin Kelley, methodically tried to take as many victims as possible as he stalked the pews of First Baptist Church.

Officials said the gunman was inside the church for a lengthy period of time, moving around freely as he gunned down people gathered for Sunday (Nov 5) morning services. One woman who was wounded during the carnage described Kelley firing at churchgoers who tried to leave, shooting round after round at those cowering or wounded on the church's floor.

David Brown, whose mother Farida was shot in her legs, said she described Kelley firing four shots into the torso of a woman on her left."With every shot, she was crying," Brown said of the woman. "She was just staring at my mom while she tried to comfort her."

As he fired rounds into the woman, Farida Brown held her hand, telling her she was heading to heaven.

When the massacre was over, more than two dozen people were fatally wounded and 20 others injured, half of them critically. Kelley was shot twice by a local man who heard what was happening and responded to the church with his own rifle. The gunman fled and ultimately shot himself in the head, officials said.

What triggered the latest rampage to cut down Americans in a public space remains unclear. Texas officials have only said that unlike other rampages at houses of worship, religious or racial animus did not motivate it.

Instead, they pointed to the gunman's rage at his relatives, saying that he had sent threatening messages to his mother-in-law; she attended the church, though she was not there on Sunday.

"There was a domestic situation going on within the family and the in-laws," Freeman Martin, a regional director with the Texas Department of Public Safety, told reporters on Monday.

The shooting in a place where gun culture is deeply rooted has prompted sharply different responses. Some residents of tiny Sutherland Springs - a tiny community southeast of San Antonio - said after the attack that it could have been stopped if people inside the church had weapons.

In Washington, Democratic lawmakers sought to force a vote on a bill establishing a select committee on preventing gun violence. Speaking in Seoul, South Korea, meanwhile, President Donald Trump asserted that tougher gun laws would not have stopped the mass shooting saying that "hundreds more" may have died had another man not been able to "neutralise" the attacker with a gun of his own.

Trump has responded to previous attacks by calling for increased immigration restrictions such as "extreme vetting," even in cases where his policies would not have stopped those attacks. When asked in Seoul whether he would support "extreme vetting" on guns, Trump said "there would have been no difference three days ago."

But how Kelley obtained his weapons has become the source of a separate federal investigation. He was convicted of domestic violence while serving in the Air Force, making him the latest mass killer with such abuse in his past.

On Monday, the Air Force said it failed to follow policies for alerting federal law enforcement about this conviction, which meant he was prohibited "from buying or possessing firearms," according to Air Force spokesperson Ann Stefanek.

While serving at Holloman Air Force Base in New Mexico, Kelley was convicted of abusing his wife and her child. He spent a year at a Navy brig in San Diego and was then kicked out of the military in 2014 with a bad conduct discharge.

Court martial documents made public on Monday state that Kelley kicked, choked and struck his wife in 2011 and 2012. He also struck her young child "on the head and body with a force likely to produce death or grievous bodily harm," according to the documents.

This information was not in the National Criminal Information Centre database, which meant that despite a law meant to keep Kelley from obtaining firearms, his gun purchases were apparently able to proceed.

He had purchased four guns since 2014, one in each year, according to federal officials. Two of those guns were purchased from a retailer, Academy Sports, after he passed federal background checks in 2016 and 2017. Kelley also passed a background check needed for a job as a security guard at a water park over the summer.

The Air Force has launched a review of his case to determine how it handled his criminal records and whether "records in other cases have been reported correctly," Stefanek said.

Police and court records across three states paint the picture of a young man with a sometimes violent private life. The same year he was discharged from the Air Force after his domestic violence conviction, Kelley was charged with a misdemeanor count of mistreatment, neglect or cruelty to animals in El Paso County, Colorado, where he lived at one point, records show.

Sheriff's deputies responded to a call about a man who was punching a dog, police records indicate. Four witnesses told deputies that they saw a man matching Kelley's description yelling at and chasing a white-and-brown husky.

Dave Ivey, who identified himself as Kelley's uncle, apologised to the shooting victims in an interview with NBC News."I never in a million years could have believed Devin could be capable of this kind of thing," Ivey said. "My family will suffer because of his coward actions."

In Sutherland Springs, which is swarmed with TV satellite trucks and reporters from around the world, people are still grappling with the scale of the attack, which tore a hole through the small community. It's a small town, so everyone knew the victims, even if they didn't know them personally.

Lorenzo Flores and Terri Smith had just pulled into pump number 3 at the Valero gas station when they saw a man in black carrying a rifle outside the church. Then they heard the gunfire.

A young man covered in blood escaped the church, sprinted across a field of grass and collapsed inside the convenience store between two aisles, gasping about a shooter killing everyone in the church.

"I might not have known everybody in there by name but I knew their face and I knew their smile," said Flores, 56, the head cook at Theresa's Kitchen, an eatery owned by Smith that is tucked into the corner of a convenience store at the gas station.

With Thanksgiving approaching, local residents are invited to a feast on Nov 19 at the community centre, which was Terri's idea. The feast will continue as planned, they said.

"We're still going to put that dinner on and I think that's going to make us a little stronger," Flores said. "At least, it helps a little. And a little is better than nothing."