By Jim Forsyth

SAN ANTONIO (Reuters) – The family of a woman and two children killed when a gunman opened fire in a rural Texas church has sued the store that sold the assault rifle used in the deadliest mass murder in the state’s history, lawyers said on Friday.

The lawsuit filed this week in a state district court in San Antonio seeks at least $25 million from Academy Sports Outdoors, accusing it of being negligent in allowing the sale of the Ruger AR-556 used to kill 26 people at Sutherland Springs First Baptist Church on Nov. 5.

The retailer was not immediately available for comment and has previously told media it conducted all the required background checks.

The suit was brought by relatives of Joann Ward, who was fatally shot along with her daughters Emily Garcia and Brooke Ward.

The lawsuit claims that when the gunman, Devin Kelley, purchased the weapon in a San Antonio store, he entered an address in Colorado Springs on the federal Firearms Transaction Record form that needs to be completed before a firearm can be sold.

He obtained the weapon in Texas but it should have been sent to his Colorado residence, where he had been stationed with the U.S. Air Force, the lawsuit said.

“The Ruger should have never been placed in Kelley’s hands in Texas,” Houston Attorney Jason Webster, lead attorney on the case, said in a statement.

Kelley had a court-martial conviction for assault, which should have permanently disqualified him from legally obtaining a gun.

But the Air Force has acknowledged it failed to enter Kelley’s 2012 domestic violence offense into a U.S. government database used by licensed gun dealers for conducting background checks on firearms purchasers.

Another family, several of whose members were killed in the shooting, has filed a negligence claim against the U.S. Air Force over its failure to enter the name into the database.

(Reporting by Jim Forsyth in San Antonio; Additional reporting by Jon Herskovitz in Austin; Editing by James Dalgleish)