The U.S. Department of Justice announced Tuesday that two Chinese nationals have been arrested on federal charges for allegedly exporting tens of millions of dollars’ worth of sensitive American microchips used in artificial intelligence applications. Authorities said one of the men was living in the United States unlawfully.

The defendants, identified as Chuan Geng, 28, of Pasadena, California, and Shiwei Yang, 28, of El Monte, California, are accused of violating the Export Control Reform Act—a serious federal offense that carries a maximum prison sentence of up to 20 years. Geng voluntarily surrendered to federal agents on Saturday, the DOJ said, while Yang was taken into custody the same day.

According to an affidavit filed in the case, prosecutors allege that Geng and Yang operated a company called ALX Solutions Inc., which they used as a front to funnel restricted U.S. technology to China.

The technology in question includes advanced graphic processing units (GPUs)—powerful computing components that play a critical role in AI development, data processing, and machine learning systems. Federal prosecutors said neither the defendants nor their company ever sought, nor were granted, the necessary licenses from the U.S. Department of Commerce to legally export such products.

Court filings note that ALX Solutions was incorporated shortly after the Commerce Department tightened licensing requirements for precisely the kind of cutting-edge microchips the men are accused of sending overseas. Investigators believe this timing was not a coincidence.