A 13-year-old boy who was swept out to sea with his mother and two siblings saved his family by swimming four kilometers (2.5 miles) to shore for help “in rough conditions,” police in Australia said.

The group were kayaking and paddleboarding off the coast of Quindalup, Western Australia, on Friday afternoon when they were carried out to sea, said the WA Police Force in a statement published on Facebook on Monday.

The boy “decided to return to shore in fading light,” and paddled a short distance in his kayak before it took on water, leaving him to swim back and alert authorities at around 6 p.m. local time (5 a.m. ET), said police.

A search and rescue operation was then launched, and a 47-year-old woman, a 12-year-old boy and an eight-year-old girl were “located by the rescue helicopter clinging to a paddleboard,” according to the statement.

“A volunteer marine rescue vessel was directed to their location and all three were successfully rescued and returned to shore,” said police.

The boy, Austin Appelbee, told CNN affiliate 9News that thinking of his family drove him on.

“I just said ‘alright. Not today, not today, not today,’” he said. “I had to keep on going.”

“The waves were massive. I did breaststroke, I did freestyle, I did survival backstroke,” Austin told the outlet.

“I hit the bottom of the beach and I just collapsed and then after that I had to sprint two kilometers to go get to the phone,” he added.

The boy’s feat was a “superhuman effort,” Marine Rescue commander Paul Bresland told 9News.

“Two hours without a life jacket on and yeah, he made it,” said Bresland.

Austin’s mother Joanne Appelbee said that all of her children had been swimming since they were young.

“I’m speechless at his efforts, but at the same time, I knew he could do it,” she told 9News.

Marine Rescue Busselton said that it was “a great outcome” in a separate statement published on Facebook on Saturday.

“Fantastic effort from all involved in trying conditions,” read the statement.

“Please be mindful of the strong offshore winds that can occur this time of year,” it added. (CNN)

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