LOS ANGELES: Grammy Award-winning rapper Nelly has been released from jail without charges pending an investigation of rape allegations, police in Washington state said.

Nelly, 42, was arrested early Saturday in Auburn, Washington, after a woman accused him of raping her on his tour bus.

Police said Nelly -- born Cornell Haynes Jr -- had been booked for investigation of second-degree rape and released from custody.

Nelly has vehemently denied the charges.

"I am beyond shocked that I have been targeted with this false allegation," he said on Twitter. "I am completely innocent. I am confident that once the facts are looked at, it will be very clear that I am the victim of a false allegation."

The sexual assault allegedly took place on the tour bus hours after Nelly had performed at the White River Amphitheater just east of Auburn.

Nelly´s lawyer also denied the charges.

"(Nelly) is the victim of a completely fabricated allegation," his attorney Scott Rosenblum told AFP in a statement.

"Our initial investigation clearly establishes this allegation is devoid of credibility and is motivated by greed and vindictiveness.

"I am confident, once this scurrilous accusation is thoroughly investigated, there will be no charges," he added.

Nelly has received 12 Grammy nominations and won three Grammy awards, including for best rap solo performance in 2003.

A native of Austin, Texas, he grew up in St. Louis, Missouri. His first three albums, released between 2000 and 2004, were all US number ones.