Heavy gunfire was heard for half-an-hour in Niger's presidential palace area early Wednesday.
The incident reported by many eye witnesses to be a possible coup attempt comes two days ahead of the swearing-in of president-elect Mohamed Bazoum.
Niger's presidential guards are reported to have foiled the operation and details remain sketchy as of now.
A resident of Niamey's Plateau district, which includes the president's official residence and offices, told AFP: "It was around 3.00 am, we heard shots from heavy and light weapons and it lasted 15 minutes before stopping, followed by shots from light weapons."
There have been growing attacks by Islamist militants, and political tensions following Mohammed Bazoum's victory in the country's February presidential election runoff. Bazoum is a former interior minister and right-hand man of outgoing president Mahamadou Issoufou, who is voluntarily stepping down after two five-year terms.
Former president Mahamane Ousmane, who lost in the runoff, has rejected the results, and alleged fraud. He called for "peaceful marches" across the country, but a planned opposition protest Wednesday (today) in Niamey was banned by authorities.
Niger has suffered numerous coups in its history- The most recent is that of February 2010 which toppled then president Mamadou Tandja.