More than 20 people have been killed in twin suicide bombings in central Niger, claimed by group MUJAO in retaliation for the country's military involvement in neighbouring Mali.
The two attacks on Thursday, one inside a military camp in the city of Agadez and the other in the remote town of Arlit inside a French-operated uranium mine, come just four months after al-Qaeda linked fighters claimed a desert gas plant attack in neighbouring Algeria that left 38 hostages dead, also in retaliation against the intervention in Mali.
The Movement for Oneness and Jihad in West Africa (MUJAO) claimed responsibility for the attacks.
"Thanks to Allah, we have carried out two operations against the enemies of Islam in Niger," Abu Walid Sahraoui, MUJAO spokesman, told AFP news agency.
"We attacked France and Niger for its cooperation with France in the war against sharia [Islamic law]."
MUJAO was also among several that seized control of northern Mali last year before being driven out by French-led intervention in the country.
El-Hassen Ould Khalil, spokesman for Mokhtar Belmokhtar of the Algerian "Signatories in Blood" group, later said the commander had "supervised" the suicide bombings in conjunction with MUJAO, according to AFP news agency.
The group on Friday threatened more attacks in Niger, according to AFP.
Thursday's attack saw 19 people killed in the desert city of Agadez, located almost 1,000km northeast of the capital, where the attackers drove their explosive-laden car past the defences at a military garrison and succeeded in entering the base, said Minister of Defence Mahamadou Karidjo.
After a fierce gun battle, security forces returned the town to calm, but one attacker was still holding soldiers hostage, military sources and local officials said, but later said there was no hostage situation.
French President Francois Hollande pledged to help Niger "destroy" the fighters and a Niger security said French special forces were involved in efforts to end the assault.
Eighteen soldiers and a civilian were killed along with four attackers at the army base, Interior Minister Abdou Labo said.
By late evening Thursday, the last member had been "neutralised", the Niger defence minister said.
"Everybody has been subdued, the operation is over," the minister told AFP.
Further north in Arlit, about 30 minutes after the first attack, a car bomb struck at the Somair uranium mine operated by run by French nuclear group Areva.
Areva said one person was killed in the attack and 14 others injured.
Niger officials said crushing and grinding units had been badly damaged at the plant and uranium production had stopped.
The mine, which produced 3,065 tonnes of uranium in 2012, makes up 30 percent of the group's uranium production globally.
"We have stopped production at the mine until further notice to allow us to assess whether the attack has caused damage in the mine," an Areva spokesman told Reuters news agency.