A counsellor described the heartbreaking sight of parents desperately searching for their children after the Texas floods which took the lives of 27 of her campers and colleagues.

Holly Kate Hurley said she will "never forget" witnessing parents realise their worst fears came true as their children weren't among a group of kids recovered amid the flooding. The youngsters had been at Camp Mystic, a girls' summer camp ravaged by the disaster. Twenty-seven girls and staff there are among those dead.

Ms Hurley, a counsellor at the camp, said today: "Seeing little girls run to their parents and just hug them and cry, and also just seeing some parents who were looking for their little girls and they weren’t there... But, that’s just a sight I don’t think I’ll ever forget.

"I was with my campers in the middle of the night, it was about 1.30 in the morning. And rain just kind of started coming through our windows. I woke my girls up, told them to close the windows and then the power just went out, all the fans turned off, running water didn’t work."

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The two employees died after bravely trying to save young girls after the Guadalupe River flooded and surged by up to 30 feet above its usual water level on Friday. Ms Hurley told Fox News the days since have been harrowing as authorities have raced against the clock in the urgent search. Ten children and one staff member remain missing.

"They told us that two of the cabins with the seven-year-old girls were wiped away and all these girls were missing. And we went back to our cabins and tried to keep up good spirits with these young girls. I think I was just in shock," Ms Hurley added.

The National Weather Service has extended a flash flood watch for the Texas Hill Country, where an additional one to three inches of rain is expected to fall Monday, until 7pm local time.

A heartbreaking photo has, meanwhile, emerged, showing the girls and counsellors who were staying in one of the cabins, which was washed away by the water. The Bubble Inn cabin, located less than 500 feet from the river, hosted 13 girls and two counsellors. The girls from the Bubble Inn cabin who are confirmed dead are Janie Hunt, Margaret Bellows, Lila Bonner, Lainey Landry, Sarah Marsh, Linnie McCown, Winne Naylor, Eloise Peck, Renee Smajstrla and Mary Stevens.

Officials have come under scrutiny as to why residents and youth summer camps along the river were not alerted sooner, but White House leaders have insisted there were no errors.