On Friday, the prime minister of the African island nation, Patrice Trovoada, said that a coup attempt was thwarted in Sao Tome and Principe and that four attackers were "neutralized" and detained.
According to the reports, at least five people died as a result of the failed coup attempt, including opposition leader Arlecio Costa, while dozens have been arrested.
Sao Tome and Principe authorities have accused the Buffalo Battalion, a South African mercenary group dismantled in 1993, of attempting to stage a coup, RFI said.
A former mercenary with the Buffalo Battalion, Costa participated in a coup attempt in Sao Tome and Principe in July 2003, and was also convicted of the 2009 coup attempt.