Sean O'Neill, a retired NYPD detective who worked on the Joint Terrorism Task Force, fatally shot his wife, Arlene O'Neill, a fifth-grade teacher, before turning the gun on himself in a murder-suicide at their Tuckahoe home. The incident occurred while their three children were present but unharmed, and they are now in the care of relatives. The couple reportedly argued the night before, which escalated into the tragic event the following morning. Arlene O'Neill was a beloved teacher in the Eastchester Union Free School District, which has initiated crisis support for students and staff. The community and family are in shock, and the incident has sparked calls for mental health resources. Sean O'Neill retired from the NYPD in 2023.