Gabon's President Ali Bongo Ondimba has been placed on house arrest, according to military officers reported by the AFP news agency. President Ali Bongo is being kept at home, with his family and doctors around him, according to a statement read on state television. One of the president's sons was arrested for "treason", the statement reportedly added.

Twelve soldiers appeared on television early on Wednesday morning, announcing they were cancelling the results of the election and dissolving “all the institutions of the republic”.

They added that the country’s borders had been closed “until further notice”.

The soldiers said they were from the Committee of Transition and the Restoration of Institutions and represent security and defence forces in the country.

One of the soldiers said on TV channel Gabon 24: “We have decided to defend peace by putting an end to the current regime.”

This, he added, was down to “irresponsible, unpredictable governance resulting in a continuing deterioration in social cohesion that risks leading the country into chaos”.

The sounds of loud gunfire could be heard in the country’s capital, Libreville, following the broadcast.

The electoral commission said Mr Bongo had won just under two-thirds of the votes in an election the opposition argued was fraudulent.