DAKAR, Senegal - A group of senior military officers in Gabon said Wednesday they were seizing power in this central African nation, overturning the results of a disputed presidential election shortly after the electoral committee announced that President Ali Bongo had won another term.

The Bongo family has led Gabon, an oil-rich nation with a population of about 2 million, for 56 years and has been accused by critics of abusing its position to accumulate massive amounts of wealth. Bongo said in a video from his residence that he was under arrest and called on the international community to “make noise.”

In a video on state television, the senior officers declared that borders were closed and that state institutions including the Senate, National Assembly and Constitutional Court were dissolved.

“We have decided to defend the peace by putting an end to the current regime,” one officer said, reading a joint statement on national television, surrounded by about a dozen others in military fatigues. “We call on the population for calm and serenity.”

Frustration with the Bongo regime ran deep, and recent elections, including the election Saturday in which Bongo won a third term, were marred by violence and allegations of rigging. As dawn broke, social media showed crowds of Gabonese on the streets celebrating the coup, waving Gabon’s flag, hugging, dancing, and singing the national anthem.

“It is too early to say its good or not good, but it can be good,” said Paulette Oyane-Ondo, a Gabonese human rights lawyer. “If it means that things will change, it will be good.”

In the video shared by BTP Advisers, the firm that advised Bongo during the election, the president appeared seated in his residence. “My son is somewhere, my wife is another place, and I’m at the [official] residence,” he said. “I don’t know what’s going on.”

The coup marks the latest in a remarkable string of mutinies in West and Central Africa, including the most recent military takeover in Niger, which became a red line for democratically elected West African leaders. Since 2021, there have also been coups in Mali, Burkina Faso, Guinea, Chad and Sudan.

The officers have announced that Gen. Brice Oligui Nguema, who was head of the Republican Guard charged with protecting Bongo, is the leader of the new junta - much as in Niger, where the head of the presidential guard seized power last month.

In comparison with Niger, Mali and Burkina Faso, where coups were fueled by fears over spiraling violence linked to Islamic extremism, Gabon is peaceful and was seen as relatively stable.

But the most recent election was widely seen as lacking credibility, Oyane-Ondo and others analysts said, citing the government’s internet shutdown and a lack of observers. Bongo was declared the winner early Wednesday, with election officials saying he had won 65 percent of the vote, compared with 31 percent for his main challenger, Albert Ondo Ossa. Shortly after that announcement, the military officers declared the coup.

Mucahid Durmaz, a senior analyst at Verisk Maplecroft, said that the military “draws legitimacy from the recent electoral process, which was practically conducted behind closed doors” and was driven by discontent among the people.

“The Gabonese people haven’t benefited from the state’s vast oil and mining wealth while the Bongo family has enjoyed absolute control over the country’s economic activities and state bureaucracy,” he said.

Some inspiration from the coup, he added, could have also come “from the Sahel, where the failure of political elites and foreign powers to curb insecurity and improve governance triggered the wave of coups in recent years.”

Bongo, who was elected in 2009, and his father, Omar Bongo, who ruled for 41 years before that, had been key allies to France, Gabon’s former colonial power, in a region in which anti-French sentiment is growing increasingly prevalent. As recently as June, Bongo had met with French President Emmanuel Macron in Paris.

On Wednesday, Olivier Véran, a spokesman for the French government, said that France “condemns the military coup underway in Gabon” and is “monitoring developments in the situation with great attention.”

France has also said that it does not accept the coup in Niger, where the democratically elected President Mohamed Bazoum remains under house arrest. The Economic Community of West African States, a 15-member bloc to which Niger belonged, has threatened military intervention to restore democracy. Analysts and regional leaders said such a reaction is unlikely for Gabon, which is not part of that group.

Human rights activist and former Nigerian senator Shehu Sani praised the coup on X, the platform formerly known as Twitter, saying that Gabon’s “father to Son Dictatorship has been overthrown.”

“Five decades of one family rule is not a democracy,” Sani said. “This is what happens when democracy is suffocated.”

The Gabonese military officers who announced the coup called themselves the “Committee of the Transition and the Restoration of Institutions” and said that “irresponsible, unpredictable governance” had resulted in a deterioration of social cohesion. The officers said in the video that they respected Gabon’s “commitments to the international community.”

In 2019, Gabon’s government foiled an attempted coup against the president, who had suffered a stroke earlier that year and left the country for an extended period for treatment.

Oyane-Ondo, the human rights lawyer, noted that this coup appeared to be substantially more organized than the 2019 attempt, which was quickly shut down by authorities. On the streets in Libreville, she said, there was surprise and elation.

“People are outside in the streets dancing, and they are very happy,” she said, “but it’s too early to tell the real vision of the situation.”

Victoire Issembe Duboze, who unsuccessfully vied for the presidency in the most recent election, said: “This military action is the best thing for Gabon because Ali Bongo was not elected by Gabon.”

“Our country is very rich. We have manganese, petrol and everything it takes to make every Gabonese happy,” she said, “but if you come to our country and you see the life of a Gabonese, it’s very bad.”

The European Union’s foreign policy chief, Josep Borrell, said Wednesday that the bloc’s foreign ministers would discuss the developments in Gabon, which he noted were part of a “very difficult situation” in the region.

“The ministers,” he said at a meeting of E.U. defense ministers in Toledo, Spain, “have to have a deep thought on what is going on there and how we can improve our policy in respect to these countries. . . . This is a big issue for Europe.”

Bisset reported from London and Ombuor from Nairobi.