TONTO NATIONAL FOREST, Arizona - Adults, teens and children as young as 2 were enjoying a summer afternoon by cooling off in an Arizona creek when the gentle waters turned deadly.

The group from the Phoenix and Flagstaff areas had met on Saturday for a day trip along a popular swimming hole near Payson, about 160 kilometers northeast of the capital. They set up lounge chairs not knowing an intense thunderstorm was dumping heavy rainfall just upstream in the Tonto National Forest.

The storm unleashed 90-centimeter-high floodwaters, dark with ash from a wildfire, onto the unsuspecting family and friends. The torrent carried away tree branches and other debris and left nine people dead.

Searchers, including 40 people on foot and others in a helicopter, recovered the bodies of five children and four adults. Authorities did not identify them.

A 13-year-old boy from the same group was still missing on Sunday.

Disa Alexander was hiking to the swimming area where Ellison Creek and East Verde River converge when the water suddenly surged.

Video she posted to social media showed torrents of water surging through jagged canyons carved in Arizona's signature red rock.

"I could have just died!" Alexander exclaimed on the video.

She spotted a man holding a baby and clinging to a tree. Nearby, his wife was also in a tree. A boy Alexander described as the couple's son was on the rocks above the water.

Had they been swept downstream, they would have been sent over a 6-meter waterfall, Alexander said.

Alexander and others tried to reach them but couldn't.

Fortunately help was close by.

Some rescuers were already near the swimming hole after getting a call to help someone who had suffered a bad allergic reaction, according to Detective Sergeant David Hornung of the Gila County Sheriff's Department.

When they arrived at the scene, "they heard someone screaming for help and saw a man clinging to a rock", said Hornung, who added that the man was safely rescued. "Then they heard other people calling for help."

Four people were rescued and taken to the hospital for treatment of hypothermia.

Some 40 rescuers in bright orange T-shirts and helmets dotted the green landscape as they combed the waters and banks for the missing boy. A few brought along specially trained search dogs hoping to find him alive, Hornung said.

While Arizona is known for its dryness, it gets bursts of heavy rains during the summer monsoon season. The severe thunderstorm was located in a remote area that had been burned by a recent wildfire. The "burn scar" was one of the reasons the weather service issued the flash flood warning.

Associated Press