The four suspects accused of plotting to bomb two Jewish sites in the Bronx and shoot down military airplanes pleaded not guilty to conspiracy charges during their arraignment Wednesday.

James Cromitie, David Williams, Onta Williams and Laguerre Payen, all of Newburgh, N.Y., face a slew of charges, including conspiracy to use weapons of mass destruction, conspiracy to acquire and use anti-aircraft missiles, and conspiracy to kill law enforcement officers and government employees.

The four men were arrested last month after allegedly planting C-4 explosives they believed to be real in front of Riverdale Temple and Riverdale Jewish Center in the Bronx. The mock explosives were provided to the suspects by an FBI informant, who also supplied them with an inactive missile. The men allegedly planned to shoot down military planes at the Stewart Air National Guard base in Newburgh.

During the arraignment at the White Plains Federal Courthouse Wednesday morning, the suspects remained calm as they pleaded not guilty to the charges. They are scheduled to appear in court Friday for a pre-trial hearing. If convicted, the four men could face life in prison.