Four men were indicted Tuesday in what prosecutors said was a plot to bomb two New York City synagogues and fire outside-to-air missiles at U.S. military planes.

The defendants - James Cromitie, 44, David Williams, 28, Onta Williams, 32; and Laguerre Payen, 27 - were charged with conspiracy to use weapons of mass destruction within the United States, conspiracy to obtain and use anti-aircraft missiles and six other counts. They face a maximum penalty of life in prison. Arraignment is planned for Wednesday.

The plot was exposed in a yearlong investigation involving an FBI informant. It ended with federal agents and New York police used an 18-wheel truck to block a vehicle carrying the suspect after they planted what they believed were explosive devices in cars near the synagogues, said New York City Police Commissioner Raymond Kelly.