Gunshots were first heard around 23H00 GMT about two kilometres away from the presidential palace.An apparentexchange of fire was also heard after midnight in the neighbourhood of Antula, on the outskirts of the capital, where an army general lives.
The gunfire continued on Friday morning, as military vehicles circulated on the streets and residents commuted to work and school.
“The presidency has nothing to do with it,” a communications assistant said, adding that there was no reaction on their behalf.
The developments follow a spate of coups in a region, which had been making strides toward shedding its reputation for military-led takeovers. Overall there have been eight coups in West and Central Africa in the last three years.
A police source said the shooting started after heavily armed soldiers stormed a police station to free Finance Minister Suleimane Seidi, arrested earlier that night.
The minister was detained over six million CFA francs ($10,050.25) allegedly disbursed from public coffers without permission, the source said. His whereabouts are currently unknown.
Seidi is a member of the former ruling PAIGC party, which leads the coalition that won a majority in legislative elections in June.
The result quashed President Umaro Sissoco Embalo’s plans to push through a constitutional change that would have allowed him to consolidate power by removing the country’s semi-presidential system. The PAIGC is opposed to this.
Embalo is attending the United Nations Climate Change Conference in Dubai, where he is expected to speak later on Friday.
There have been at least 10 coups or attempted coups in Guinea Bissau since independence from Portugal in 1974. Only one democratically elected president has completed a full term in the West African nation of around 2 million inhabitants that sits between Senegal and Guinea.
At least six people were killed during a failed attempt to overthrow Embalo in February last year.
At the time, Embalo suggested it was linked to the government’s fight against drug trafficking rather than an army plan to seize power.
Sierra Leone’s government pushed back a military attempt to overthrow it over the weekend. More than 20 people were killed as gunmen in the capital Freetown attacked military barracks, a prison and other locations on Sunday, freeing about 2,200 inmates.