The President of Burkina Faso, Roch Kabore, has reportedly been detained by mutinying soldiers.
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, however, denied suggestions of a military coup or that the president was under arrest.
President Kabore was detained at a military camp by mutinying soldiers, foreign media reports say.
Soldiers also surrounded the state television headquarters.
Hundreds of people have come out in support of the soldiers despite a government-imposed curfew. Some of them set fire to the ruling party's headquarters.