At least 20 people have been killed in the latest mass shooting in the United States.

The massacre happened at a Walmart store near the Cielo Vista Mall in El Paso, Texas, a few miles from the US-Mexican border.

At least 26 people, including children, are being treated at local hospitals for their injuries.

A young white man is in custody and is believed to be the sole gunman.

He has been named by US media as 21-year-old Patrick Crusius, a resident of the Dallas area.