ARLINGTON, Va. – A death investigation in the East Falls Church neighborhood has been ruled a homicide-suicide following a determination of cause and manner of death by the Office of the Chief Medical Examiner.
At approximately 5:18 p.m. on December 7, 2023, police were dispatched to the 2400 block of N. Powhatan Street for the report of a check on welfare. Upon arrival, officers made entry into the residence and located an adult male and female deceased inside with signs of intentional carbon monoxide poisoning.
The deceased were identified as Maria Theista MacKnight, 72, and Gregory Cunningham, 72, of Arlington, VA. They were married.
Following the discovery of the deceased, the Department’s Homicide/Robbery Unit immediately initiated a death investigation. In March 2024, the Office of the Chief Medical Examiner ruled the manner of Ms. Theista MacKnight’s death a homicide, with the cause being carbon monoxide poisoning. Mr. Cunningham’s death was ruled a suicide, with the cause being carbon monoxide poisoning.
This remains an active investigation and anyone with information related to this incident is asked to contact the Arlington County Police Department’s Homicide/Robbery Unit at 703-228-4180.