The protests began on Saturday outside Niamey's grand mosque with police using tear gas a day after at least four were killed in the second city of Zinder
In the wake of the Charlie Hebdo shootings, at least two churches have been set on fire in the capital of Niger amid fresh protests against French magazine depicting the Prophet Muhammad.
The protests began on Saturday outside Niamey's grand mosque with police using tear gas a day after at least four were killed in the second city of Zinder.
The French Embassy has warned its citizens to stay indoors.
Last week, two gunmen linked to al-Qaeda, killed 12 people at the magazine's Paris offices and there were attacks in Paris which killed another five people, four at a Jewish supermarket.
The cover of the magazine's latest edition, published after the attack, featured a cartoon of the Prophet Muhammad weeping while holding a sign saying "I am Charlie".
Many Muslims see any depiction of Islam's prophet as offensive.
In Niger, a former French colony, hundreds of demonstrators gathered at Niamey's grand mosque, shouting "God is Great" in Arabic.
At least two churches were set on fire - similar to Friday's demonstration in Zinder where protesters also raided shops that were run by Christians.
The French cultural centre in Zinder also came under attack.
The centre's director, Kaoumi Bawa, said an angry crowd of around 50 people had smashed the building's door and set fire to the cafeteria, library and offices.