Search and rescue operations are ongoing. State emergency personnel are aiding local search and rescue operations "around the clock" as they search for potential survivors in Texas, Gov. Greg Abbott said.

The first weather emergency alert sent by the National Weather Service with urgent language instructing people to "seek higher ground now" was sent at 4:03 a.m. local time.

Emergency responders continue to search for missing people and local police said efforts have been slowed by "sightseers who are making things worse."