UPDATE 5:10 p.m.
A law enforcement official says at least 15 people were killed in the attack at an El Paso shopping center and that the suspect who was taken into custody is 21-year-old Patrick Crusius.
The official was not authorized to discuss an ongoing investigation publicly and spoke to The Associated Press on condition of anonymity. The official also stressed that the death count is preliminary and that the investigation is still ongoing.
Police say most of the victims of Saturday's attack appear to have been at a Walmart near the Cielo Vista Mall in El Paso, though they say the mall had also been "secured."
El Paso hospitals say they are treating 22 victims, not including a patient who died after arriving at one of the hospitals.
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Authorities say the Walmart in El Paso where a gunman opened fire was packed with back-to-school shoppers.
Sgt. Robert Gomez said at a news conference that anywhere from 1,000 to 3,000 shoppers and about 100 employees were at the Walmart near the Cielo Vista Mall when Saturday's attack happened.
Gomez says most of the victims appear to have been at the Walmart, though he also says police had "secured" the mall. He says a man in his 20s was taken into custody and that law enforcement didn't fire a single shot.
UPDATE 3:30 p.m.
A University Medical Center of El Paso official says one of 12 people who were rushed to the hospital after the attack on a shopping complex has died.
Ryan Mielke, a hospital spokesman, says all of the victims suffered traumatic injuries in Saturday's attack at or near the Cielo Vista Mall. He declined to provide additional details about the victims, including the one who died.
Mielke says two children, ages 2 and 9, were stabilized at the medical center before being transferred to the neighboring El Paso Children's Hospital.
Authorities say multiple people were killed in the attack, but they haven't said how many were killed or wounded. They say they believe it was carried out by a single male suspect who has been taken into custody.
President Donald Trump tweeted, "Reports are very bad, many killed."
EARLIER:
Multiple people were killed and one person was in custody after a shooter went on a rampage Saturday at a shopping mall, police in the Texas border town of El Paso said.
Police responded in the early afternoon to an active shooter scene at the Cielo Vista Mall, which is near Interstate 10 on the east side of the city, and were advising people to stay away from the area.
Shortly after, Sgt. Enrique Carrillo, a police spokesman, said a suspect was in custody and there was no longer danger to the public.
El Paso, which has about 680,000 residents, is in West Texas and sits across the border from Juarez, Mexico.
Presidential candidate and former congressman from Texas Beto O'Rourke appeared a bit shaken as he appeared at a candidate forum in Las Vegas on Saturday shortly after news of the shooting in his hometown was reported.
O'Rourke said he had called his wife before taking the stage and said the shooting shatters "any illusion that we have that progress is inevitable" on tackling gun violence.
The Democrat said he'd heard early reports that the shooter might have had a military-style weapon, saying we need to "keep that [expletive] on the battlefield and do not bring it into our communities."
"We have to find some reason for optimism and hope or else we consign ourselves to a future where nearly 40,000 people a year will lose their lives to gun violence, and I cannot accept that," O'Rourke said.
Texas Gov. Greg Abbott called the shooting "a heinous and senseless act of violence" and said the state had deployed a number of law enforcement officers to the city.
A family of three was one of a dozen waiting outside a local bus station, trying to get back to their car, in blocked-off Walmart parking lot.
"I heard the shots but I thought they were hits, like roof construction," said Adriana Quezada, 39, who was in Walmart with in the women's clothing section with her two children.
She said she saw four men, dressed in black, wearing shirts, moved together firing guns indiscriminately.
"I saw four men, shooting everywhere," Quezada said "I told my son, those are gunshots."
Her daughter, 19, and son, 16, threw themselves in the ground, then ran out of the Walmart through an emergency exit. They were unhurt.
White House staff said President Trump was briefed on the shooting and spoke about it with Attorney General Barr and Governor Abbott.
Check back for further details.