DAKAR, Senegal (AP) — Human Rights Watch says Cameroon's military has forcibly deported at least 100,000 Nigerian asylum seekers to slow down the spread of Islamic extremism.

The rights group said Wednesday the deportations defy a request by the U.N. Refugee Agency to protect refugees and not force any returns to Nigeria until the "security and human rights situation has improved considerably." It said the Nigerians sent back face more violence, destitution and further displacement.

The group's report says Cameroonian soldiers have tortured, assaulted and sexually exploited Nigerian asylum seekers in border areas.

Cameroonian authorities deny forcing Nigerian asylum seekers to return or committing any abuses against them.

Cameroon contributes to a multinational force meant to stamp out the Nigeria-based extremists who have been staging attacks around the Lake Chad region.