During the massacre, Thompson and his Hiller OH-23 Raven crew, Glenn Andreotta and Lawrence Colburn, stopped a number of killings by threatening and blocking American officers and enlisted soldiers of Company C, 1st Battalion, 20th Infantry Regiment, 11th Brigade, 23rd Infantry Division. Additionally, Thompson and his crew saved a number of Vietnamese civilians by personally escorting them away from advancing United States Army ground units and assuring their evacuation by air. Thompson reported the atrocities by radio several times while at Sơn Mỹ. Although these reports reached Task Force Barker operational headquarters, nothing was done to stop the massacre. After evacuating a child to a Quảng Ngãi hospital, Thompson angrily reported to his superiors at Task Force Barker headquarters that a massacre was occurring at Sơn Mỹ. Immediately following Thompson's report, Lieutenant Colonel Frank A. Barker ordered all ground units in Sơn Mỹ to cease search and destroy operations in the village.