Lessing went on to serve as the East German Ambassador to Uganda. He and his third wife were killed during the Fall of Kampala in 1979, as Tanzania and its Ugandan rebel allies occupied Uganda's capital and overthrew dictator Idi Amin. Lessing and his wife attempted to escape the city amid the fighting at 04:00 on 11 April, but as they drove by a golf course UNLF insurgents fired two rocket-propelled grenades at Lessing's and a following car, destroying both and killing the four occupants.