Tehran, Iran — A senior Iranian prosecutor has accused three Americans who were detained on the border with Iraq of espionage.
It's the first signal that Tehran intends to put the three on trial.
Secretary of State Hillary Rodham Clinton is calling for their release, saying "there is no evidence to support any charge whatsoever."
The state news agency IRNA quotes Tehran's chief prosecutor as saying investigations are continuing and an "opinion" on their case "will be given in the not distant future."
It's not clear from his comments whether formal charges have been made. In Iran, indictment and trial often take place behind closed doors.
The three graduates of the University of California, Berkeley, were arrested July 31 after straying over the Iranian border from northern Iraq. Their families say there were on a hiking vacation and crossed accidentally.
The timing of the announcement raises the possibility that Iran is using the case to pressure the United States amid the negotiations over its nuclear program.
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