According to local police, no one was injured in the explosion which went off early Thursday at Half Mile neighbourhood of the city.
Limbe will host Group F AFCON matches involving Tunisia, Mali, Mauritania and Gambia.
Separatist fighters who have vowed to disrupt AFCON in the city said on social media they were responsible for the blast and stressed that it was “a warning sign of what we will do during AFCON”.
Separatist leaders had said they do not want AFCON matches to take place in a region “at war”.
Cameroon army has deployed additional ammunitions and troops to the region.
The troops undertake routine day and night patrols.
Separatists had since 2017 been clashing with government forces in Anglophone regions of Southwest and Northwest where they want to create an independent nation they call “Ambazonia”.
AFCON will officially begin on Sunday in the capital Yaounde and will run for four weeks.