Four men have been charged in New York with arranging to ship to China and Iran weapons or a substance that can be used in uranium enrichment.

Three of the men have been arrested. The fourth is in being sought.

The conspiracy charges are contained in indictments unsealed Wednesday in federal court in Manhattan. The head of the FBI office in New York says the shipment of carbon fiber was a violation of U.S. laws regardless of the motivation.

A U.S. official says the scheme was shut down as part of the government’s “cat and mouse” game with people who try to ship sensitive military-grade technology overseas.

The defendants include two Iranian nationals, a Turkish citizen and a U.S. citizen. Two were held in U.S. custody. Bail was set for a third.