Two DC-7 planes flying on a locust-control mission on behalf of the United States Agency for International Development were attacked en-route from Senegal to Morocco by POLISARIO troops who may have mistaken them for Moroccan military C-130 aircraft.
One crashed, killing all 5 on board, the other managed to land despite losing an engine [1] In 1988, an American team was mobilized as part of a locust control mission in West Africa.
On December 8 of the same year, two planes owned by T&G Aviation were commissioned by the United States Agency for International Development to spray the locusts.
The main aircraft (N284) lost an engine and a wing, and then crashed near the Moroccan Western Sahara Wall, killing all 5 crew members on board.
[1] The other aircraft (N90804) lost an engine and a part of a wing but managed to land in Sidi Ifni.