Quick action by security forces foiled the coup and five of the plotters were arrested, government spokesman Guy-Bertrand Mapangou, told Radio France International.
A fifth suspect was on the run, Reuters reported, after soldiers announced plans for a "national council of restoration", in the oil-rich country, where the ruling Bongo family has been dogged by accusations of corruption and fraud during almost a half-century in power.
"It reinforced doubts about his ability to assume the responsibilities of his role as President of the Republic", said Lt Kelly Ondo Obiang, the leader of the so-called Patriotic Movement of the Defence and Security Forces of Gabon.
Even though the government has just announced the putschists' arrest and the end of this coup, this event shows the political uncertainty in Gabon since October 2018 when the president, who is now recovering in Morocco, had a cerebrovascular accident.
President Ali Bongo who is now recovering from a stroke in Morocco took over the country's rulership from his father, Omar Bongo, who ruled Gabon for 42 years before his death in 2009.
USA troops deployed to the central African nation of Gabon last week in response to potential violence in neighboring Democratic Republic of the Congo (DRC) remain committed to their mission despite prospective unrest linked to a failed coup attempt on Monday.
The Gabonese government said Monday it has quashed a coup attempt in the country.
Canadians held in China since arrest of Huawei executive
The advisory also warned of the "coercive" practice of exit bans, when authorities prevent people from leaving China. In Beijing, China's top prosecutor said Thursday that the two Canadians had "without a doubt" violated the law.
The leaders of the attempted coup read out a statement on state radio in the pre-dawn hours denouncing Bongo.
Internet access was also briefly cut on government instructions, said an employee of Canal+, one of the main internet providers.
He promised to put all of his efforts into improving the quality of life of Gabon's people.
Gabonese President Ali Bongo Ondimba is recuperating from an ailment in Morocco.
As Monday's coup attempt played out, African Union Commission Chairperson Moussa Faki Mahamat issued a statement saying the African Union "strongly condemns the coup attempt this morning in Gabon". His family has ruled the oil-producing country for almost half a century. His family has ruled the oil-rich country for over half a century.
Bongo became ill in October while on a visit to Saudi Arabia. His constitutional powers were recently transferred to the Prime Minister and Deputy President. President Donald Trump told US Congress on Friday the first of about 80 troops arrived in Gabon last Wednesday to protect American citizens and diplomatic facilities if violence breaks out in the DRC capital, Kinshasa.
Bongo was re-elected in 2016 as the President of Gabon with narrow margins of votes in a poll marred by violent protests and fraud.