Federal prosecutors acknowledged a possible translation error in a key piece of evidence used to arrest and detain a mosque leader accused of supporting terrorism.

Yassin Muhiddin Aref 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 said was found in a terrorist camp in northern Iraq in summer 2003. The indictment said an Arabic entry referred to Aref as a "commander" and listed his former address and phone number in Albany.

But FBI translators who have a copy of the original entry say the phrase means "brother," prosecutors told the judge in a letter.

Aref is the imam of the Masjid as-Salam mosque in Albany. Also charged earlier this month in the sting operation was Mohammed Mosharref Hossain, 49, one of the mosque's founders. They face 70 years in prison if convicted.

Defense attorneys say that the translation error undermines the entire government case, and that both men should be released on bail. U.S. Attorney Glenn Suddaby said that authorities are unsure which translation is correct but that it does not change the case.