Patrick Crusius is alleged to have killed 20 people and injured dozens after opening fire at an El Paso Walmart.
Twenty people were killed and more than two dozen injured when a gunman opened fire at a Walmart in El Paso, Texas, on Saturday.
At least seven of those killed were Mexican nationals and police are calling the attack a “hate crime” after discovering the alleged shooter’s online manifesto.
The alleged gunman, 21-year-old Patrick Crusius has been charged with ‘capital murder’ over the mass shooting – an offence that can carry the death penalty in Texas.
"The suspect has been charged for capital murder," El Paso police spokesperson Sergeant Robert Gomez told a news conference.
Prosecutors have also deemed the mass shooting a case of domestic terrorism.
"We're treating this as a domestic terrorist case," John Bash, the US Attorney for the Western District of Texas, told reporters.
Police are still piecing together exactly what happened, but the Mexican government has announced seven of the 20 people killed in the mass shooting were Mexican nationals.
Seven Mexicans killed
"Unfortunately it is confirmed that there are seven Mexicans who lost their lives," Mexican President Andres Manuel Lopez Obrador said on Sunday.
Mexico’s Foreign Relations Secretary Marcelo Ebrard tweeted the names of the seven who died: Sara Esther Regalado; Adolfo Cerros Hernández Aguascalientes; Jorge Calvillo García; Elsa Mendoza de la Mora; Gloria Irma Márquez Juárez; María Eugenia Legarreta Rothe; Ivan Filiberto Manzano.
Mexican authorities also confirmed a man, a woman and a child were also wounded in the attack but survived.
Mario de Alba Montes, 45, was shot in the back, while 44-year-old Olivia Mariscal Rodriguez and 10-year-old Erika de Alba Mariscal suffered multiple gunshot wounds.
All are being treated at the UMC Hospital in El Paso.
In El Paso, situated on the border with Mexico, more than eight in 10 residents are of Hispanic descent.
The accused shooter had come from Dallas with the apparent intent of inflicting mass carnage and had reportedly posted a race-themed manifesto detailing the “Hispanic invasion” of the US online before the alleged attack.
Among the 20 dead was a 25-year-old woman who was shot while shielding her two-month-old son, her sister says.
Leta Jamrowski, 19, learned on Saturday afternoon that her sister Jordan Anchondo had been fatally shot at Walmart in El Paso while shopping for back-to-school supplies.
Ms Jamrowski spoke to The Associated Press as she paced a waiting room at the University Medical Centre of El Paso, where her two-month-old nephew was being treated for broken bones - the result of his mother's fall.
"From the baby's injuries, they said that more than likely my sister was trying to shield him," she said. "So when she got shot she was holding him and she fell on him, so that's why he broke some of his bones. So he pretty much lived because she gave her life."
Ms Anchondo was the mother of three children.
Ms Jamrowski spent the night desperately awaiting word of whether her brother-in-law, Andre Anchondo, had survived the attack.
"They said that if he were alive, more than likely he would have gotten in contact by now," she said.
Mr Anchondo's death has not been confirmed by authorities.
Sixty-year-old ‘Nino’ Arturo Benavides has been confirmed among the dead, with his goddaughter telling CBS News he was at the cash register when the gunman entered the Walmart and opened fire.
It's believed the US Army veteran had been shopping with his family when the shooting broke out.
Jessica Coca Garcia and Memo Garcia
The pair were also among the wounded, according to the Associated Press.
Norma Coca told Kansas TV station KWCH her daughter and son-in-law were near the entrance of the Walmart when the shooting started.
She said Ms Garcia, was in stable condition after being shot three times in the leg and her son-in-law remained in a critical condition with gunshot wounds to the leg and back.