No charges will be filed against American swim star Michael Phelps from his being photographed with a pipe typically used to smoke marijuana, police announced on Monday.

Richland County Sheriff Leon Lott said that after a full investigation into the November party at which Phelps was photographed to touch off a controversy that led to a three-month ban, there was not enough evidence to charge anyone.

"Having thoroughly investigated this matter, we do not believe we have enough evidence to prosecute anyone that was present at the November party," Lett said.

Phelps, who won a record eight gold medals at the Beijing Olympics six months ago, was shown holding a bong in a photograph published two weeks ago by a British newspaper, humiliating the superstar swimmer.