Mutinous troops have reportedly detained the President of Burkina Faso, Roch Kabore.
Some troops in the West African nation have demanded the sacking of military chiefs and more resources to fight Islamist militants.
Gunfire had been heard overnight near the presidential palace and at barracks in the capital, Ouagadougou.
The government on Sunday denied suggestions of a military coup or that the president was under arrest.
The president’s location is unknown, but AFP news agency quoted security sources as saying that he and other government ministers are at the Sangoule Lamizana barracks in the capital.
There has been no communication from President Kaboré himself since Sunday night, when he posted on social media congratulating the national football team on their win in an Africa Cup of Nations match.