In any case, Amin decided to forestall Obote and strike first. In the early morning hours of 25 January 1971, mechanized army units loyal to him attacked strategic targets in Kampala and the airport at Entebbe, where the first shell fired by a pro-Amin tank commander killed two Roman Catholic priests in the airport waiting room. Amin's troops easily overcame the disorganized opposition to the coup, and Amin almost immediately initiated mass executions of Acholi and Langi troops, whom he believed to be pro-Obote.