In El Paso, the suspected gunman, Patrick Crusius, a 21-year-old white man from Allen, Texas, near Dallas, is in police custody. The police are reviewing a "manifesto" in connection with the shooting, The Washington Post reported.

The shooter fired a military-style rifle into the crowd shortly after 10:30 am at a Walmart store in a popular commercial district, the El Paso Herald-Post reported. Video footage posted on social media showed a chaotic scene in which people were running and crying.

When it occurred, the store was packed. Between 1,000 and 3,000 shoppers and more than 100 store employees were present because of the back-to-school season, El Paso Police Sergeant Robert Gomez told reporters.