According to court documents, in August 2017, while Xiong was living in Oroville, Xiong mailed a letter to a company in Sunnyvale, informing the company that Xiong and others were going to bomb the location. The bomb threat was reported to the Sunnyvale Police Department who responded to the scene to investigate, and ultimately reported the incident to the FBI. The letter was identified as one of approximately 150 letters Xiong mailed between January and December 2017, containing false information about bombings and assassinations. Although the U.S. Postal Service intercepted many of the letters, others were delivered to the intended recipients who were located across the United States, including FBI offices, an airport, a mall, and the current and former presidents of the United States.
Xiong was arrested on Dec. 22, 2017, and remained in custody until May 23, 2018, which is approximately 153 days. Xiong pleaded guilty on Jan. 3, 2019.
This case was the product of an investigation by the Federal Bureau of Investigation, the U.S. Secret Service, and the U.S. Postal Inspection Service. Assistant U.S. Attorney Shelley D. Weger prosecuted the case.
-- Eastern District of California
Source: U.S. Secret Service