The National Weather Service began sending flash flood warnings that should have triggered cellphone alerts a little after 1 a.m., while local officials began posting on Facebook about four hours later.

Rescuers searched the Guadalupe River for survivors of the Texas floods that killed more than 100 people over the July Fourth holiday weekend, with an unknown number of people still missing. The basin area was crowded with families and campers preparing to enjoy the holiday when pounding rain brought about catastrophic flash floods just before dawn Friday.

A young camper in Texas shared with Scripps News what he experienced as the Guadalupe River started to flood cabins on July 4.

Six counties reported deaths from multiple severe flood events since Friday, July 4. Also, Kerrville officials reported that a privately owned drone collided with a helicopter conducting search and rescue operations.

Flash floods in Texas have killed more than 100 people, many of them children. Heavy rains fell quickly in the predawn hours Friday in the Texas Hill Country.