The 44-year old from Indiana, his wife and son were caught up in the unrest between the armed Anglophone movement and the largely Francophone central government.
Military spokesman Col. Didier Badjeck said the military killed at least four suspects in Wesco's death and arrested many others.
The attacks happened the day after 85-year-old President Paul Biya was declared the winner for the seventh term which intensified the unrest.
Wesco and his wife, Stephanie, had just moved to Cameroon two weeks ago.
Wesco was reported unconscious after the attack and doctors were unable to revive him at the hospital.