Military officers have announced on national television in Gabon that they have taken power, annulling the results of Saturday’s election, in which President Ali Bongo was declared the winner.

The electoral commission said Mr Bongo had won just under two-thirds of the votes in an election the opposition described as a `fraud orchestrated’ by the ruling party.

They cancelled the election results and dissolved “all the institutions of the republic”.

The mutinous soldiers, if successfully overthrow President Ali Bongo, that would end his family’s 53-year hold on rein of power in Gabon.

Gabon is one of Africa’s major oil producers, while nearly 90% of the country is covered by forests.

This is even as Mr Bongo has been placed under house arrest surrounded by his family and doctors, according to a broadcast by military officers.

They said he would be replaced by the head of the presidential guard, General Brice Oligui Nguema, and that certain members of the government would “answer for their actions” following an investigation by the “competent authorities”.

This is the eighth coup in former French colonies in Africa in the past three years.

The French government has condemned the takeover, with a spokesman calling for the election results to be respected.

“France is closely monitoring the development of the situation on the ground,” said Olivier Veran.

Russia and China are among the other countries that have expressed their concern.

The European Union’s foreign policy chief said a military takeover would increase instability in Africa.

“This is a big issue for Europe,” said Josep Borrell.