At least 24 people have died after heavy rain pounded Kerr County, Texas, early Friday, leading to "catastrophic" flooding, the sheriff said.

Teams conducted dozens of rescues, and the emergency response continued as an unknown number of people remained unaccounted for.

Texas Lieutenant Governor Dan Patrick said authorities were searching for 23 girls listed as unaccounted for among more than 700 children who were at a summer camp when it was swept by floodwaters.