Detective Adrian Garcia said in an arrest warrant affidavit that Patrick Crusius, 21, emerged with his hands up from a vehicle that was stopped at an intersection shortly after last Saturday's attack and told officers, "I'm the shooter."

Crusius later agreed to speak with detectives, telling them that he had driven to El Paso from the Dallas suburb of Allen and that he was targeting Mexicans in the attack.

Authorities believed that shortly before the attack, Crusius posted a racist screed online that railed against an influx of Hispanics into the United States.

According to the authorities, Crusius has been charged with capital murder and is being held without bond. Federal prosecutors have said they are also considering hate-crime charges.

Meanwhile, El Paso police department said Friday that Crime Scene Unit continue to process the scene at Walmart Cielo Vista. "It is a lengthy and meticulous process that will likely take a few more days to complete. We do it with the victims and justice in mind," the police department tweeted.

A total of 22 people, including eight Mexican nationals, were killed and more than twenty others injured in the attack that happened last Saturday morning in a Walmart mall in the largely Latino border city of El Paso.

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