Authorities in the English-speaking West African country -- which has been going through a political crisis following elections in June this year -- have declared a national curfew until further notice.
President Julius Maada Bio said late Sunday that calm had been restored after what he described as an attempt to undermine peace and stability in the country.
"Most of the leaders have been arrested. Security operations and investigations are ongoing," Bio said on national television, adding that the government would "ensure that those responsible are held accountable."
President Julius Maada Bio said late Sunday that calm had been restored after what he described as an attempt to undermine peace and stability in the country.
"Most of the leaders have been arrested. Security operations and investigations are ongoing," Bio said on national television, adding that the government would "ensure that those responsible are held accountable."
An AFP journalist said calm was slowly returning to the capital by Sunday evening, but checkpoints heavily guarded by security forces remained in place.
Videos posted on social media appeared to show men in uniform under arrest in the back or beside a military pick-up truck.
Earlier in the day, witnesses told AFP they heard gunshots and explosions in the city's Wilberforce district, where the armory and some embassies are located.
Other witnesses reported exchanges of fire near a barracks in Murray Town district, home to the navy, and outside another military site in Freetown.
The information ministry reported attacks on prisons earlier in the day that obliged the security forces to retreat.
"The prisons were thus overrun" with some detainees released and others "abducted," it said.
Video posted on social networks suggested numerous prisoners had escaped from the central jail.
One man who was in a group filmed on the street by an AFP correspondent said they had escaped from the prison.
The information ministry said security forces had pushed the attackers to the outskirts of Freetown, with drone video taken by AFP showing empty streets in the capital.
The situation remained unclear with the authorities making no comments on the motives or identity of the attackers.
'Like a war'
President Bio wrote on X, formerly Twitter, that the government would "continue to protect the peace and security of Sierra Leone against the forces that wish to truncate our much-cherished stability."
"We remain resolute in our determination to protect democracy in Sierra Leone."
Regional bloc the Economic Community of West African States (ECOWAS), which has contended with a series of coups among its members since 2020, issued a statement underlining "its zero-tolerance for unconstitutional change of government."
Echoing language used to condemn past coup attempts, ECOWAS spoke of its "utter disgust" over a "plot by certain individuals to acquire arms and disturb the peace and constitutional order."
The US embassy condemned on social media the bid to break into the armoury and offered continued support for those "working for a peaceful, democratic, healthy and prosperous Sierra Leone."
The European Union's local representation expressed concern and called for the respect of constitutional order.
Witness Susan Kargbo told AFP by telephone she was woken "by a loud sound of heavy machine gun (fire) and bombs coming from the Wilberforce barracks around 4:30 am.
"I was shocked and... the gunshots continued until this morning, it was like a war," she said.
Attackers 'repelled'
The government said those attempting to break into the armoury had been repelled but asked the public to stay at home while security operations continued.
The local representations of the UK and the European Union echoed the authorities' advice to stay at home.
The civil aviation authority said Sierra Leone's airspace remained open but asked airlines to reschedule their flights after the lifting of the curfew.
President Bio, who was first elected in 2018, was re-elected in June with 56.17 percent of the vote -- just over the 55 percent needed to avoid a run-off.
International observers condemned inconsistencies and a lack of transparency in the count, as well as acts of violence and intimidation.
The main opposition All People's Congress (APC) party disputed the results of the presidential, legislative and local elections on June 24 and boycotted all levels of government.
The APC and the government signed an agreement in October following talks mediated by the Commonwealth, the African Union and ECOWAS.
The APC agreed to end its boycott and begin participating in government in exchange for an end to detentions and court cases it said were politically motivated.
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