Witnesses in Mali say heavy gunfire has broken out in the capital, Bamako, about a month after a military coup d'état.
The witnesses say the shoot-out on Monday involved troops who took part in the March coup and presidential guard members loyal to Mali's deposed president Amadou Toumani Toure.
A spokesman for the military government said the soldiers from the presidential guard are trying to stage a counter coup.
Witnesses say that presidential guard members have set up barricades at strategic points around Bamako. They say one of the sites where gunfire was reported is around the state broadcaster's main building.
State television did not broadcast its usual evening newscast on Monday.
On March 22, renegade soldiers seized power in Mali, accusing President Toure of failing to properly equip the army to handle a Tuareg rebellion in the north.
The new military government, under pressure from the regional bloc ECOWAS, later agreed to form a civilian transitional government to organize new elections.
Last week, Mali's interim leaders announced the formation of a new government that gave military officers three posts in the new government, defense, interior security and interior ministry. The rest of the 24-member government is made up of civilians.
Since the coup, Tuareg rebels fighting alongside the Islamist group Ansar Dine have captured three northern regions. The rebels declared an independent state, a move that was rejected by neighboring countries and the African Union.