Rebels want more of the mineral profits from Niger's north
Rebels in Niger have freed four French workers they kidnapped from a uranium mine, handing them to the Red Cross.
The aid organisation said it would take the four to the capital Niamey and hand them to the authorities on Thursday.
The Niger Movement for Justice (MNJ) snatched the group, who work for French nuclear firm Areva, on the weekend in the northern town of Arlit.
The MNJ, led by the nomadic Tuareg people, is fighting for a larger share of northern Niger's mineral wealth.
For several months, the north of the country has been in a state of emergency and cut off from the rest of the country.
The government recently promised to provide military protection for uranium mines and oil installations.
The MNJ said on its website that the kidnapping was intended to show that the government could not live up to its promise of protecting foreign workers.
The Tuareg-led rebels are calling for greater development in the area and a larger share of the profits from the increasingly lucrative uranium mines.
But the government dismisses them as drug smugglers, arms traffickers and bandits with no political agenda.
The two sides have frequently clashed, with the government ruling out talks until the rebels disarm.
The area on the fringes of the Sahara desert, known as the Sahel, is becoming increasingly violent, the BBC's Will Ross says.
In Mali, Tuareg rebels are fighting a similar conflict. They are holding at least 50 soldiers hostage. The MNJ itself is thought to be holding eight soldiers captive.
With the demand for nuclear fuel increasing, the price of uranium has shot up and Niger's resource is in great demand.
In the past France had a monopoly on the uranium mines, but recent contracts have been signed with several other countries, including China.