A former Air Force intelligence officer who had agreed to testify before Congress about alleged secret government UFO programs died of an accidental drug overdose in May 2024, a state medical examiner found, a ruling that directly contradicts a congressman's public description of the death as a suspicious suicide and sits at the center of a new push for an FBI investigation.
Matthew James Sullivan, 39, of Falls Church, Va., died May 12, 2024, from a lethal combination of alcohol, alprazolam, cyclobenzaprine, and imipramine, the New York Post reported, citing the Northern Virginia District Office of the Chief Medical Examiner.
Alprazolam is the generic name for Xanax; cyclobenzaprine is a muscle relaxant; imipramine treats anxiety and bedwetting in children.
The manner of death was ruled accidental, not suicide, as a Republican congressman had publicly described it.
Rep. Eric Burlison, R-Mo., told Fox News in April that Sullivan "suspiciously committed suicide" within two weeks of being scheduled for a congressional interview on UFOs.
An April 16 letter Burlison sent to FBI Director Kash Patel, obtained by the Post, asked the bureau to open an inquiry citing "implications for national security." Sullivan "was preparing to provide testimony to Congress," the letter stated, and "the sudden and suspicious circumstances surrounding his death raise significant concerns about potential foul play."
The FBI said in a statement it "is spearheading the effort to look for connections into the missing and deceased scientists," working with the Department of Energy, the Department of War, and state and local law enforcement.
The bureau did not confirm or deny a specific investigation into Sullivan's death.
Sullivan earned a Bronze Star for valor in Operation Enduring Freedom and served at the Air Force Intelligence Agency, National Air and Space Intelligence Center, and National Security Agency, according to a funeral home obituary.
Burlison has stated publicly that the Intelligence Community Inspector General assessed a report tied to Sullivan's case as "credible and urgent" using statutory language under the Intelligence Community Whistleblower Protection Act, and referred it to the FBI.
The ICIG told the Post it "can neither confirm nor deny the existence of any ongoing or potential investigations."
Sullivan's case sits within a broader congressional inquiry into more than a dozen deaths and disappearances of scientists and officials tied to classified aerospace and defense programs.
House Oversight Committee Chair Rep. James Comer, R-Ky., and Burlison have sent letters to the FBI, NASA, the Department of War, and the Department of Energy seeking briefings by April 27.
Burlison confirmed that David Grusch, the retired Air Force officer who testified before Congress in 2023 about alleged government UFO possession and later reported receiving death threats, had been helping Sullivan prepare to come forward before Sullivan's death.
Jim Thomas ✉
Jim Thomas is a writer based in Indiana. He holds a bachelor's degree in Political Science, a law degree from U.I.C. Law School, and has practiced law for more than 20 years.
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