The Senegalese army says about 100 of its soldiers from the peacekeeping mission in The Gambia have tested positive for coronavirus.
The military contingent composed of 600 soldiers were returning home.
They have been quarantined in Toubacouta, on Senegalese territory near the border with The Gambia, as a precautionary measure.
Those who tested positive are asymptomatic. More tests are being done.
The peacekeeping mission in The Gambia, deployed by regional bloc Ecowas in 2012, has mainly Senegalese soldiers.
It was deployed to force former Gambian President Yahya Jammeh to hand over power to his elected successor Adama Barrow and to assist the new Gambian administration to address security challenges.
The mission’s mandate was extended during the last Ecowas meeting at the request of President Barrow.