Kun Shan Chun is a former FBI electronics technician who is native to China and a naturalized citizen of the U.S. Chun received and responded to requests from Chinese nationals and government officials; disclosing information such as FBI surveillance strategies, FBI personnel and structure data, and FBI technological capabilities. He was arrested in March of 2016, and was sentenced to 24 months in prison and a $10,000 fine.
(From: https://www.justice.gov/usao-sdny/pr/former-fbi-employee-sentenced-manhattan-federal-court-24-months-prison-acting-agent)