Search teams are sifting through mounds of debris in Texas Hill Country as hopes of finding more survivors dimmed five days after flash floods tore through the region, killing at least 119 people including many children.

As of Tuesday evening (Wednesday AEST), there were more than 170 people still unaccounted for, according to figures provided by Texas Governor Greg Abbott. Searchers have not found anyone alive since Friday.

Most of the fatalities and missing people were in Kerr County.

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The county seat, Kerrville, was devastated when torrential rains lashed the area early on Friday, dropping more than 300mm of rain in less than an hour and swelling the Guadalupe River to a height of nearly nine metres.

The death toll in Kerr County was 95 as of Wednesday morning, Sheriff Larry Leitha told reporters at a briefing, including three dozen children.

Officials grilled over warning sooner

That figure includes at least 27 campers and counsellors from Camp Mystic, a Christian girls’ summer retreat on the banks of the Guadalupe.

Authorities have warned the death toll will likely keep rising as floodwaters recede.

Elsewhere on Tuesday, three people died in New Mexico, two of them young children, when a flash flood swept through the village of Ruidoso in mountains around 215km southeast of Albuquerque, the state’s largest city.

The flooding was sparked by heavy rain that fell on wildfire burn scars, causing a rapid runoff of water that saw the Rio Ruidoso River rise to a record 20 feet, five feet higher than its previous historical high, the village said in a statement.

Public officials in Texas have faced days of questions about whether they could have warned people sooner, giving them time to move to higher ground ahead of the raging floodwaters.

At Wednesday’s briefing, the sheriff was again pressed to address questions about how long it took for officials to respond to “Code Red” alerts about the flash flooding during the early hours of July 4.

Climate change to blame

He declined to respond directly, saying his focus was on finding the missing victims and that a full analysis of what went wrong with the response would come later.

“We will answer those questions,” he said.

“I can’t tell you when - a week or two, okay? We’re going to get to them. We’re not trying to deflect them.”

Scientists say climate change has made extreme flood events more frequent and damaging by creating warmer, wetter weather patterns.

Kerrville City Manager Dalton Rice has said the amount of rainfall exceeded predictions and fell so fast that there was not enough time to order evacuations without further endangering people.

Abbott said on Tuesday that the Texas legislature would convene a special session later in July to investigate the emergency response and provide funding for disaster relief.