The body of a swimmer that went missing Saturday was pulled from Hamilton Pool Sunday morning.

The body has been identified as that of Peter Cho, an Austin resident.

"He was a fine citizen, a fine son," his father Don Cho said. "And you cannot ask more for a son than he is. And it just breaks my heart. I cannot believe this is happening to my family."

The search, involving six agencies, started Saturday after the 21-year-old, who was swimming with friends, went under water and didn't return to the surface.

STAR Flight, Austin, Lake Travis and Travis County agencies all responded to the call.

Divers searched for Cho for some time Saturday night, and started again Sunday morning.

Don Cho raised concerns that Hamilton Pool, like many area swimming holes, has no lifeguards, and noted that many had trouble getting a cell phone signal to call for help during the incident.

"If we don't do something about it. There's going to be another family just like us crying — promising young men," he said. "No more."

The Travis County Sheriff's Office said that according to witnesses, Cho may have been coming back to land after feeling he had swam out too far. The department hopes this tragedy will serve as a warning for people this swimming season.

"Don't overestimate your [swimming] abilities," said Roger Wade, Public Information Officer for the Travis County Sheriff's Office. "Always err on the side of caution. If you are even a remotely marginal swimmer, wear a life jacket."

Cho was a senior majoring in biology at the University of Texas. He was on track to graduate next month before heading to medical school.

Hamilton Pool is closed until further notice.