MOSCOW, November 9 (RIA Novosti) - Three U.S. citizens arrested in Iran for illegally entering the country from Iraq have been charged with espionage, the Iranian news agency IRNA reported on Monday.

"They [the Americans] are accused of espionage. The investigation of the three [U.S.] citizens continues, and the results will be announced soon," Tehran general prosecutor Abbas Jafari Dolatabadi was quoted as saying by IRNA.

Shane Bauer, Sarah Shourd and Joshua Fattal were arrested on July 31 this year by border guards near the cross-border settlement of Marivan in Iranian Kurdistan. They had visas to enter Iraq and Syria, but not Iran.

Their supporters and the U.S. government maintain they were hiking in a scenic area of northern Iraq when they unknowingly entered Iran.

The White House has demanded their release and Secretary of State Hillary Clinton reiterated the U.S. position on Monday, saying Washington believed there was no evidence to support the charges.