Prisoners working in a nearby park helped save three boys whose kayak overturned in a Washington state creek, fire officials said Thursday.

Three brothers -- ages 8, 10 and 16 -- were floating down Salmon Creek near Salmon Creek Regional Park Wednesday afternoon when their kayak overturned, Clark County Fire District 6 Chief Jerry Green told NBC News. The park is in Washington state just north of Portland, Ore.

Ten prison inmates from the Larch Corrections Center near Yacolt, Wash., were doing park maintenance when they heard screams for help and responded quickly, fire officials told The Columbian newspaper in Vancouver, Wash.

Inmate Nelson Pettis, 37, jumped into the strong current, floating downstream until he could grab the two younger boys and help them to a pile of floating debris, according to the newspaper.

"I don't think I was thinking at all," Pettis told The Columbian. "I was just really concentrating on getting them to safety."

Inmate Larry Bohn, 29, helped Pettis with the rescue: "They (the boys) were saying thank you repeatedly. They just seemed really scared," he told the newspaper.

The 16-year-old boy was able to swim to shore, Green told NBC News.

Inmate Jon Fowler, 28, waited for the rescue team to arrive and helped them inflate their rescue boat, The Columbian reported. Members of the Vancouver, Wash., Fire Department and Clark County Fire District 6 were part of the rescue team.

The water was "very cold" and estimated to be moving at 25 mph, Green said. The brothers were treated for mild hypothermia, but otherwise there were no other injuries, he said. Two of the inmates were also treated for hypothermia, Portland, Ore., NBC affiliate KGW reported.

Bohn and Pettis reportedly had taken off their shirts, wrapping them around the kids to keep them warm, The Columbian reported.

The boys' names were not released.

Green said he was "extremely impressed" with the prisoners' efforts and the fact that they jeopardized their safety.

"(They) stepped up and did what was the right thing to do," Green said.

"I don't think we're heroes by any means," inmate Fowler told The Columbian. "I think we just did what any good person would do."

Nancy Simmons, a spokesperson for the Larch Corrections Center, told NBC News the brothers want to thank the inmates who helped and a meeting with their family is in the works.

This correction facility houses inmates who are not there for violent crimes and who generally have four years or less left on their sentences, Simmons said.

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Colleagues and loved ones are remembering a 50-year-old man who died while trying to save two boys in Lake Michigan as a devoted father and skilled pediatric surgeon.

Dr. Donald Liu, a father of three, was on an outing with his family in Berrian County Mich., on Sunday morning when he saw two boys struggling to swim in the lake after falling off a kayak. Liu jumped into the lake but the strong rip current below pulled him under.

The boys, who were friends of the family, made it back to land but the doctor drowned.

Liu's wife, Dr. Dana Suskind, fondly remembered her husband as a dedicated surgeon, father and husband.

"It was horrible," Suskind told the Chicago Tribune. "He had the biggest heart. He was a brilliant surgeon … but what was amazing about him was that he was the best father, that was his priority in life, and he loved me with all of his heart."

The couple, married 17 years, met at the University of Pennsylvania where Liu was a third-year surgery resident and Suskind, also a surgeon, was an intern. 

His skill for performing minimally invasive surgery and his work ethic garnered admiration from colleagues at University of Chicago Comer Children's Hospital.

They said he took on the hardest cases, helping sick children with cancer and other ailments, NBCChicago.com reported.

"He was a tireless, selfless physician," said Dr. John Alverdy, executive vice chairman of the department of surgery at the university. "He'd wake up at 2 a.m. to save a child from a gunshot wound, sleep for two hours and then be back here at 6 a.m. to do rounds and elective surgeries."

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Liu joined the university in 2001 and was named chief of pediatric surgery and surgeon-in-chief at the hospital six years later. He had recently been awarded a "distinguished clinician" award.

"It lightened the atmosphere in the room and they were more open to you and all of a sudden you could see their faces light up,"  nurse practitioner Christopher Speaker said about how Liu interacted with sick children.

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His peers echoed the same sentiment. 

"The fact that Don would save everything to save a child is what made him who he was. This doesn't surprise any of us," Liu's colleague, Dr. Jeffrey Matthews, told NBCChicago.com.

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