The regional bloc of West African states has condemned what it called an attempted coup in Guinea-Bissau amid reports of soldiers seizing control of a central area of the country's capital.
Witnesses and diplomats in Bissau described explosions and heavy arms fires in Bissau late on Thursday night, with the home of Carlos Gomes Junior, the outgoing prime minister and presidential hopeful in runoff elections scheduled for later this month, coming under attack.
"It was attacked with rocket-propelled grenades and we were forced to retreat," said a police officer who had been on guard at Gomes' residence.
Gomes' wife told the AFP news agency on Friday that her husband had been arrested by troops who attacked his residence the night before.
"He was arrested yesterday [Thursday] by some soldiers. They put him into a pickup truck and then sped off to an unknown destination," Salome Gomes said.
A diplomat, speaking on condition of anonymity, told the Associated Press news agency that the whereabouts Raimundo Pereira, the country's interim president, were unknown.
An AFP correspondent reported that the military had taken control of the ruling party headquarters and national radio station, with rocket fire and shots also being heard.
"Last night there was a very large presence of the military in the streets," Peter Thompson, the head of the UK electoral observation mission, told Al Jazeera from Bissau.
"It did seem quite co-ordinated last night in terms of how the roads were shut off... Today the streets are very calm, the city is much quieter than it normally would be. People are staying home.
"I do know that the army has taken control of the state media and state television, and they haven't released anything official," he said.
Daniel Kablan Duncan, Ivory Coast's foreign minister, told reporters after a meeting of the 15-nation Economic Community of West African States (ECOWAS) in the Ivorian capital Abidjan that the group condemned the "coup".
"We have received some difficult information from Guinea-Bissau, and this information indicates to us that there is a coup under way," he said.
"ECOWAS formally and rigorously condemns such an attempted coup d'etat."
Portugal, Guinea-Bissau's former colonial ruler, appealed for calm on Friday.
"The government is following the events in Guinea Bissau with great concern," a foreign ministry spokesperson said. "The Portuguese government is appealing for a halt to the violence and respect for the law."
Appeal for aid
Attending the ECOWAS meeting, Mamadu Djalo Pires, the foreign minister of Guinea-Bissau, appealed for international aid.
"The situation is serious. The soldiers are occupying the streets," Pires told Reuters. "I spoke to the interim prime
minister [Adiato Djalo Nandigna] and she said she was under fire", he added.
After the gunfire and explosions, armed soldiers stopped journalists from approaching the residence of the former prime minister.
Soldiers also blocked the main roads in and out of the coastal capital, one witness said. The gunfire later subsided, but frightened government officials and residents kept to their houses.
Resident Edmond Ajoye, an employee of a Dutch NGO, said he was around five kilometres from his home when the shooting began.
"There was panic. Women were running," he said. "There were rockets being launched, and the soldiers were shooting with guns mounted on their trucks."
"The soldiers took downtown," he continued. "The shooting lasted from 7:00pm until 9:00pm. They then went from embassy to embassy to make sure that the politicians couldn't seek refuge there."
Soldiers were also reported to have been posted outside the United Nations office in the capital.
Guinea-Bissau was due to hold a runoff election on April 29, pitting Gomes against former president Kumba Yala.
Guinea-Bissau's opposition - led by second-placed Yala, who claims the first round vote was rigged - have called for a boycott of the vote and warned against campaigning.
The five main opposition candidates, including Yala, said during a joint news conference on Thursday evening that the boycott would be in the name of justice.
Guinea-Bissau has weathered successive coups and attempted coups since gaining independence from Portugal in 1974.
The election is being held after the death of former leader Malam Bacai Sanha, who died in January after being rushed to Paris for treatment for end-stage diabetes.
Last Saturday, the United Nations Security Council urged candidates and voters to "exercise restraint" and "resolve their disputes in accordance with the constitutional framework".
They underscored the importance of successful elections to progress on peace-building priorities including demobilising troops and police, fighting drug trafficking and promoting national reconciliation.
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