Authorities in the island country of Sao Tome and Principe have thwarted a coup attempt overnight, the prime minister and west Africa's regional bloc say.
The Gulf of Guinea country's military barracks came under attack shortly after midnight, Prime Minister Patrice Trovoada told a press briefing aired on private broadcaster Radio Somos Todos Primos.
"We were targeted by an attempted coup, which began around 00.40 and was completed... shortly after 06.00," he said.
Four attackers were "neutralised" and detained, and the National Assembly's ex-president Delfin Neves was arrested on Friday morning, Trovoada added.
"Everything indicates (that the coup occurred under) the command of some personalities", he added.
A former soldier, Arlecio Costa, has also been detained in relation to the coup.
The head of west Africa's main regional bloc ECOWAS, Guinea-Bissau President Umaro Sissoco Embalo, condemned the coup attempt on Friday.
"Sao Tome and Principe is a country considered a model of parliamentary democracy in Africa," he tweeted.
The former Portuguese colony, located off the western equatorial coast of central Africa, has been relatively stable since an attempted military coup against the government of President Fradique de Menezes in 2003.
Coup leaders at the time said they tried to topple the regime due to widespread poverty.