A key piece of evidence against a jailed mosque leader accused of supporting terrorism has come into question, with federal prosecutors acknowledging that a note found in a terrorist camp may have been mistranslated.

Yassin Muhiddin Aref (search) is charged with aiding a government informant in a sting operation involving a fake plot to buy a shoulder-fired missile to assassinate a Pakistani diplomat.

The translation discrepancy stems from a notebook that the FBI (search) said was found in a terrorist camp in northern Iraq last summer. The indictment said an entry in Arabic script referred to Aref as a "commander" and listed his former address and phone number in Albany.

However, FBI translators now have a copy of the original entry and disagree with the earlier conclusion, saying the word was in the Kurdish language, not Arabic, and actually means "brother," prosecutors told the judge in a letter.

Aref is the imam of the Masjid As-Salam (search) mosque in Albany. Also charged earlier this month in the sting operation was Mohammed Mosharref Hossain, 49, one of the mosque's founders.

The notebook was cited last week by Magistrate David Homer as part of his rationale for refusing to set bail for Aref.

Defense attorneys say the translation error undermines the entire government case, and that both men should get out on bail. "It's a travesty," lawyer Terence Kindlon said.

U.S. Attorney Glenn Suddaby said authorities are not yet sure which translation is correct, but said it doesn't change the case.

"It doesn't change their behavior. It doesn't change the significance of where this notebook was found," he said Tuesday.

Aref, a native of Kurdistan, and Hossain, who is from Bangladesh, face up to 70 years in prison if convicted.

Also Tuesday, prosecutors said they would try to restrict the release of some information relating to the case.

"The United States believes that disclosure of this material would raise issues of national security that the court should address before any of this material is provided to the defense," Suddaby said in a court filing.