Several people have died and others are missing after flash flooding hit parts of central Texas on Friday morning.

Disaster declarations have been issued for the Hill Country and Concho Valley regions.

Rescues and evacuations have been underway since the early morning, but there are warnings of more potential flash flooding to come.

“Even if the rain is light, more flooding can occur in those areas,” Acting Governor Dan Patrick said.

Texas Governor Greg Abbott said the state was providing “all necessary resources to Kerrville, Ingram, Hunt and the entire Texas Hill Country dealing with these devastating floods”.

The region is to the north-west of the Texas city of San Antonio.

Pictures show the deep flood waters swamping bridges and fast moving water swirling down roads.

Exactly how many people have died or are missing has not yet been confirmed by authorities.

“Folks, please don’t take chances. Stay alert, follow local emergency warnings, and do not drive through flooded roads,” Texas Department of Agriculture Commissioner Sid Miller said.

Kerr County Sheriff’s Office said the area had suffered a “catastrophic flooding event” and confirmed that fatalities had been reported.

It told residents near creeks, streams and the Guadalupe River to move to higher ground.