Soldiers in Burkina Faso have attempted to stage a mutiny and talks are under way to resolve the situation, the military government has said.
After heavy gunfire was heard in parts of the capital, the country's leader, Lt Col Paul-Henri Sandaogo Damiba, urged the population to remain calm.
It is unclear if a coup attempt was in progress.
The current junta overthrew an elected government in January, citing a failure to halt Islamist attacks.
But Lt Col Damiba's administration has not been able to quell the jihadist violence. On Monday, 11 soldiers were killed when they were escorting a convoy of civilian vehicles in the north of the country.
It was the second large-scale deadly attack this month.
Who is Lt-Col Damiba?
Before dawn on Friday morning, shots and explosions were heard in the capital, Ouagadougou, some of them coming from near the presidential palace and main military barracks.
After sunrise, the normally bustling city was largely deserted, with soldiers on the streets blocking some roads and guarding key strategic points.
State television had stopped broadcasting and more gunfire was heard later in the day.
There were concerns that a second coup this year was under way. But in a statement on Facebook, Lt Col Damiba said there was a "confused situation" created by "mood swings" among some soldiers.
Urging people to remain calm and avoid social media speculation, the military leader said that "negotiations [were] under way to bring back calm and serenity".
Earlier, a government source told the BBC that a mutiny had been attempted.
In January, Lt Col Damiba ousted President Roch Kaboré, saying that he had failed to deal with growing militant Islamist violence.
"We have more than what it takes to win this war," the junta chief said when he was sworn in as president in February.
But many citizens do not feel any safer and there have been protests in different parts of the country this week.
On Friday afternoon, some protesters took to the capital's streets calling for the removal of Lt Col Damiba.
"I'm here to demand [his] departure.. because he is unable to manage the country's current situation," one protester told the Reuters news agency. "He... said he was going to restore security in the country but to this day not even one village has been retaken by the government."
"Since he's taken power our military are falling a lot and he is not sad about it," another protester is quoted as saying.
The Islamist insurgency broke out in Burkina Faso in 2015, leaving thousands dead and forcing an estimated two million people from their homes.
The country has experienced eight successful coups since independence in 1960.