El Paso Suspect Ordered Gun and Moved Out in Weeks Before Attack

After going to the local college for two years, he moved out of his grandparents’ home and “was trying to decide what he was going to do next,” Mr. Ayres, the family lawyer, said. He said he could not say where Mr. Crusius had been living, but said the family had not had a falling out and had stayed in regular contact with him.

But there was one development that concerned his mother: Her son had recently ordered a military-style weapon. Her call to the Allen Police Department was first reported by CNN.

“It was an informational call based off of his age, maturity and lack of experience handling a weapon,” said Mr. Ayres, who said the police told her that, according to the law, her son was allowed to have the weapon. “It was in no way, shape or form something that was out of concern of him being a threat.”

Sgt. Jon Felty, a spokesman for the Allen Police Department, said the police had found no records of the call from Mr. Crusius’s mother, and had done an extensive search of their records and turned up no threats or arrests.

One of the fundamental questions of the shooting is still unanswered: how and when the suspect became radicalized. He said he spent a lot of time on the computer, and a manifesto connected to him appeared on the site 8chan, a go-to resource for violent extremists.

By last weekend, the authorities said, Mr. Crusius had made the long drive to El Paso, a border town that is 80 percent Hispanic. The police said he got lost in the city and stopped at the Walmart because he had been hungry.

As the deaths of 22 people gripped the nation, and were shortly followed by another mass shooting in Dayton, Ohio, Mr. Crusius’s community in Texas encouraged one another via social media not to give the suspect added attention.

“You can refer to the terrorist’s manifesto to receive truthful insight on the reasoning behind this attack,” one former classmate said in a message. “That is the clearest and most informative evidence as to what kind of person would do something like this.”