BUFFALO, N.Y. -- Six alleged members of a terrorist sleeper cell in suburban Buffalo pleaded innocent Tuesday to charges they trained at an al-Qaida camp in Afghanistan attended by Osama bin Laden.

The six Americans of Yemeni descent were arrested just days after the Sept. 11 anniversary. They are from Lackawanna.

A federal grand jury indicted them Monday on two counts of providing material support to a foreign terrorist organization. The charges carry a penalty of up to 15 years in prison.

Authorities said the charges are largely based on allegations that in the spring 2001 they attended the terror camp, where bin Laden declared that there "is going to be a fight against Americans."

Prosecutors said the men were awaiting orders from bin Laden's group to carry out an attack in the United States. However, prosecutors acknowledged there was no evidence the men posed an imminent threat.

Only one of the men, Sahim Alwan, 29, was granted bail. He is awaiting release on $600,000. The five others -- Yahya Goba, 25; Yasein Taher, 25; Faysal Galab, 26; Shafal Mosed, 24; Mukhtar al-Bakri, 22 -- are being held without bail.

At an Oct. 8 ruling, a federal magistrate credited Alwan with extricating himself from the camp and distancing himself from its activities by feigning an ankle injury.