The tragedy in El Paso came just six days after a teenage gunman opened fire with an assault-style rifle on a crowd attending the annual Garlic Festival in Gilroy, California, killing three people and injuring a dozen others before he was shot by police and ultimately took his own life.
He said he was shopping in a sports store when a child came into the store saying there was an active shooter at the nearby Walmart.
The Walmart was full of shoppers buying back-to-school supplies at the time of the attack.
Walmart has been secured and the criminal investigation has started Gomez said.
"It's not what we're about", he said at the news conference with Gov. Greg Abbott and the police chief. Two helicopters patrolled the areas from the sky as well monitoring the situation.
Thirteen people were taken to University Medical Center of El Paso, spokesman Ryan Mielke told CNN, and one of them has died.
Eleven victims were transported to the Del Sol Medical Center, hospital spokesman Victor Guerrero said.
Miami Valley Hospital spokeswoman Terrea Little said 16 victims have been received at the hospital, but she couldn't confirm their conditions.
At least 23 are still being treated in hospitals, authorities said.
"From the baby's injuries, they said that more than likely my sister was trying to shield him", she said.
"Our thoughts are with the victims and their families".
"We have multi reports of multiple shooters. police conducting search of a very large area", the department wrote on Twitter.
He was taken into custody after he surrendered to the police outside the Walmart. Officers patrolling the area responded in less than a minute to the shooting, which unfolded around 1 a.m. on the streets of the downtown Oregon District, Mayor Nan Whaley said. It is understood no shots were fired by police during his arrest.
Cory Brooker, senator for New Jersey, said on CNN's "State of the Union" that Trump was "responsible because he is stoking fears and hatred and bigotry".
He added there were initially incorrect reports that another attack was also taking place at another mall.
President Donald Trump described the El Paso attack as "an act of cowardice" and police are treating it as a possible hate crime.
Update, 8pm: Police said 20 people have been killed and 26 are wounded following the mass shooting. Working with State and Local authorities, and Law Enforcement. Two federal law enforcement sources and one state government source confirmed the suspect's identity. "God bless you! Mad respect in Atlanta!"
Democratic presidential candidate Beto O'Rourke made a statement during a presidential forum in Las Vegas, Nevada.
"I can tell you that the investigators are doing their best to complete this investigation proper with the respect and dignity that the victims deserve", Gomez said. "He said I was fine".
"We are going to aggressively prosecute it both as capital murder but also as a hate crime, which is exactly what it appears to be", Texas Governor Abbott told reporters.
The carnage ranked as the eighth-deadliest mass shooting in modern USA history, after a 1984 shooting in San Ysidro, California, in which 21 people died. We have deployed troopers, special agents, Texas Rangers, tactical teams, and aircraft to the scene in a support role.
Hamza bin Laden was very threatening to US
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