Federal authorities on Wednesday accused a Korean-American businessman of working for North Korea in a quest to obtain “top secret” documents and recruit agents who would infiltrate the U.S. government.

One day after he was arrested without incident at his townhome in Santa Monica, Calif., John Joungwoong Yai, 59, appeared in U.S. District Court in Los Angeles on charges that he knowingly served as a North Korean agent without notifying the U.S. government of his action.

Yai and his wife, Susan Youngja Yai, also were charged with two counts of lying to U.S. Customs officials by failing to declare $18,179 — in $100 bills — that authorities allege a North Korean official paid to Yai during clandestine April 2000 meetings in Prague and Vienna.

For more than seven years, Yai has been under investigation by FBI counterintelligence officials.