Texas Gov. Greg Abbott warned Sunday that additional rounds of heavy rains lasting into Tuesday could produce more life-threatening flooding.

The death toll from catastrophic floods in Texas reached at least 78 on Sunday, including at least 28 children, as the search for girls missing from a summer camp entered a third day and fears of more flash flooding as rain fell on saturated ground prompted fresh evacuations.

Although Kerr County was hit hardest by flooding, at least seven others have been confirmed dead in different parts of Texas. About 150 miles east of Camp Mystic, Travis County has confirmed at least four deaths, county spokesperson Hector Nieto told CBS News by phone Saturday night. Travis County includes the Texas capital city of Austin.