A downpour in the scenic Texas Hill Country quickly turned catastrophic in the early morning hours of the July Fourth holiday.

The torrential rain that brought destruction to a children’s summer camp and other holiday spots in rural Texas came with devastating speed. Water came crashing through the stone cabins of Camp Mystic in the early hours of Friday with little warning as the girls and staff slept.

Flash flooding killed at least 80 people in Central Texas, and dozens are still missing. Here’s how you can help.