POMPANO BEACH (CBSMiami) – A member of the Austrian National Swim Team was seriously injured Sunday night during a trip to the beach on the team’s day off. Police say he dug a deep hole in the sand, jumped in, and to the horror of those around him, the hole collapsed.

The scene unfolded on Pompano Beach Sunday evening, in the sand along 100 North Ocean Boulevard. Pompano Beach Fire Rescue spokesperson Sandra King said the 19 year-old man taking a break from practice with the team dug a hole about the size of a grave, 7 feed deep and 6 feet wide, and then jumped in.

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The sand was unstable, and after he jumped in, King said the hole collapsed around him, trapping him inside.

Special rescue units were called in to help dig the man out, and firefighters supplied him with oxygen while they worked, but it was a slow process in the shifting sand. Rescuers had to use construction vehicles to dig the sand out around the trapped man.

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“Obviously, 7 feet deep and 6 feet around is just amazing,” King said. “Basically, the only thing that came out was his head.”

The man was completely immobilized by the sand, witnesses said.

King said the man apparently started digging the hole for fun, as members of his swim team looked on. Then, he jumped in, and things went terribly wrong.

“His friends tried to get him out,” King said, “his coach tried to get him out, but they could not get him out and he could not move.”

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Witnesses say it took almost 3 hours to get the man out of the sand, and about 8:30, he was rushed to North Broward General Medical Center in critical condition. His name was not immediately available, but his friends, who gathered at the hospital, said they believe he will be OK after treatment.