At least 135 people died in central Texas, including more than three dozen children, after strong downpours sparked flash flooding at the beginning of the July 4 holiday weekend.

Recovery teams have been combing the banks of the Guadalupe River in Kerr County, the epicenter of the deadly flooding, hoping to find the bodies of those still missing, which last week was estimated to be near 100.

"The Kerr County Flood Disaster Joint Information Center can confirm that three individuals remain missing at this time from the July 4 flood disaster," the county said in a statement late Saturday.

"Extensive follow-up work" had determined that many individuals originally listed as missing had been verified as safe, it said.

"We are profoundly grateful to the more than 1,000 local, state and federal authorities who have worked tirelessly in the wake of the devastating flood that struck our community," said Kerrville City Manager Dalton Rice.

"Thanks to their extraordinary efforts, the number of individuals previously listed as missing has dropped from over 160 to three."

Dozens of deaths were reported in other counties, with the body of at least one person in Burnet County, a local fire chief, yet to be found.

The flooding of the Guadalupe River was particularly devastating for summer camps on its banks, including Camp Mystic, where 27 girls and counselors died.

US President Donald Trump toured the devastation on July 11 with his wife Melania, as his administration faced questions over its response in the immediate aftermath and plans to devolve federal emergency management to states.