At least 59 people have died after heavy rainfall caused flash flooding in parts of central Texas on Friday, authorities have said.

Rescue operations are ongoing in Central Texas after flash flooding along the Guadalupe River left 23 to 25 girls from Camp Mystic unaccounted for. Officials say dozens have died as catastrophic floods continue to ravage the Hill Country.

At least 51 people, including 15 children, were killed, with most of the deaths coming in Kerr County in the state’s Hill Country.