"A Texas Army National Guard Soldier assigned to Operation Lone Star has gone missing along the river during a mission related incident, Friday April 22, 2022 in Eagle Pass, Texas," the Texas National Guard said in a press release.
The solider has not been found, but existing reports of a fatality are inaccurate at the moment, the release said.
The Texas National Guard, including state and federal law enforcement, are working quickly to find the missing solider, the release added.
US media reported, citing multiple sources, the soldier had drowned while trying to save migrants themselves drowning in the river.
Several hundred National Guard troops are currently deployed to the US southern border to help the Customs and Border Protection (CBP) deal with the record number of migrants coming to the United States illegally.