Soldiers in Guinea-Bissau have arrested the country's prime minister after sealing off large areas of the capital, a military press attache has said.
Francelino Cunha said Carlos Gomes Jr had been held a day after soldiers attacked his home with grenades. The whereabouts of interim president Raimundo Pereira remain unknown.
Military leaders earlier issued a statement saying they intervened simply to halt foreign aggression, claiming Mr Gomes was going to allow Angolan troops inside Guinea-Bissau.
The body representing West African nations, Ecowas, has called the violence "a reprehensible coup attempt".
Desire Kadre Ouedraogo, the president of the Ecowas commission, said: "The commission firmly denounces this latest incursion by the military into politics and unreservedly condemns the irresponsible act, which has once more demonstrated their penchant to maintain Guinea-Bissau as a failed state."
Portugal, the former colonial ruler of the tiny African nation, appealed for the violence to stop and advised Portuguese citizens to stay inside their homes. It said the situation in Bissau was "still uncertain".
Explosions blasted through the capital of the coup-prone nation on Thursday night, according to a diplomat and witnesses.
The violence overshadows a looming presidential run-off vote, which Mr Gomes was favoured to win. There have been fears of a coup since Guinea-Bissau's president died of complications from diabetes in January, leaving Mr Pereira in charge of the chronically unstable country known for cocaine trafficking.
A military official said the soldiers had encircled the home of Mr Gomes and attacked the building with grenades. It was not clear if the premier was at home when the shooting started.