Tchiani, head of the presidential guard since 2011, read a statement on national TV as the "president of the National Council for the Safeguard of the Homeland," presenting the coup as a response to "the degradation of the security situation" linked to jihadist bloodshed.
The guard which instigated the coup detained Bazoum and his family in the presidential palace. A group of soldiers who later appeared on state television said they had stripped him of power.
He is said to be in good health and has been able to talk by telephone to other heads of state.
The Economic Community of West African States (ECOWAS) has condemned the power grab and demanded Bazoum's "immediate release," saying he "remains the legitimate and legal President of Niger."
France's President condemned the coup in Nigeria today, while his foreign minister said the power grab there was not final and that those responsible still had time to accede to international demands that ousted president Mohamed Bazoum be reinstated.
Emmanuel Macron, speaking during a visit to Papua New Guinea today, called the coup “completely illegitimate and profoundly dangerous, for Nigeriens, for Niger and for the whole region.”
Speaking to reporters on the sidelines of his trip, foreign minister Catherine Colonna also said that ECOWAS was likely to meet on Sunday with a discussion on imposing possible sanctions – which she said Paris would support.
She referred to the “attempted” coup d’etat, saying that it is not yet definitive. Colonna said President Bazoum “must be restored to his constitutional functions.” Colonna said there are “ways out” for the coup plotters who respond to global condemnation of Bazoum's ouster.
Colonna said President Macron had spoken to him on Friday and that he was in good health and should be released as a condition of restoring constitutional order.
Insecurity has remained a problem since Bazoum was elected in 2021 as jihadists that took root in Mali in 2012 gained ground, killing thousands and displacing over 6 million across the Sahel.
Niger is a key ally of Western countries against Islamist insurgencies in West Africa and a number of foreign troops are based there, including French and American.
This story is developing.
Information for this report came from Reuters and AFP.