The El Paso Police Department gave a second media briefing following a mass shooting at a Texas Walmart.
Sergeant Robert Gomez did not give casualty and fatality figures but said there had been at least one fatality.
"As of right now, like I confirmed earlier, we do have one person in custody. I can confirm that it is a white male in his 20s," Gomez said.
He was asked about reports that the suspect posted a right-wing manifesto.
"I don't have any information on the manifesto," he replied.
He also did not confirm reports that the suspect was armed with an AK-47 variant assault rifle.
Gomez said that no officers discharged their weapons while apprehending the suspect, which occurred "without incident."