Johannesburg - The US military has opened an inquiry into allegations that Cameroonian troops carried out torture and murder at a base where American troops were present, a US spokesperson said on Friday.
Amnesty International last month said it had documented 80 cases of abuse by Cameroonian troops at their Salak base in the country's Far North region.
Amnesty alleged the abuses were carried out between 2013 and 2017 against people suspected of involvement with Nigeria-based Boko Haram extremists.
Amnesty said US troops were present at several locations within the Salak base, headquarters of Cameroon's Rapid Intervention Battalion.
Colonel Mark Cheadle, a spokesperson for the US Africa Command, said a "commander's inquiry" has been launched to determine if any US troops were aware of any of the alleged abuses.
Cameroon's government has criticised the Amnesty report.
Most of the cases investigated by Amnesty International involved men 18 to 45 years old, though the group documented the mistreatment of some women, children and people with mental and physical disabilities.
"Detainees were severely beaten with various objects including electric cables, machetes and wooden sticks," suspended from poles and subjected to drowning, the report said, adding that many were deprived of food, water and medical attention.
Several people interviewed said they had witnessed deaths after torture.
Boko Haram's insurgency has killed more than 20 000 people and displaced 2.7 million in northeastern Nigeria and neighboring countries of Cameroon, Chad and Niger.
The countries all contribute to a multinational force to combat the insurgency.