A California man allegedly worked as a spy for the Chinese government from 2015 to July 2018, according to charges unsealed by the Department of Justice on Monday. Xuehua Peng, also known as Edward Peng, 56, acted as a courier—executing dead drops, delivering payments, and personally bringing “secure digital cards containing classified information” to China, according to a DOJ press release. Peng, a resident of Hayward, conducted at least five successful “dead drops” over the course of the three years, according to the complaint. The dead drops, which occurred in California and Georgia, involved Peng booking hotel rooms and leaving a room key to be picked up by an unnamed source. “Peng then left envelopes of cash in the room, retrieved a secure digital card left there by the source, or both,” according to the DOJ.

“The conduct charged in this case alleges a combination of age-old spycraft and modern technology,” said U.S. Attorney David L. Anderson for the Northern District of California. “The charges announced today provide a rare glimpse into the secret efforts of the People’s Republic of China to obtain classified national security information from the United States.” If convicted, Peng faces a maximum sentence of 10 years, and a fine of $250,000 for acting as an agent of a foreign government.