Tuareg-led rebels in Niger handed over four French hostages to the Red Cross this evening after holding them captive for three days.
The Red Cross said it hoped to transfer them to Niger authorities tomorrow.
"We have just handed over, in a safe location ... the four French nationals to the Red Cross," the rebel Niger Justice Movement (MNJ) said in a statement posted on its website.
The MNJ has said it seized the four French nationals, working for the French nuclear group Areva, to disprove the Niger government's assurances that it would guarantee the safety of foreign investors in the West African country.
"They are well and should be leaving for France very soon," the French company said in a statement issued in Paris.
Juan Coderque, of the International Committee of the Red Cross (ICRC) regional office in Senegal, told Reuters: "We can confirm that the four French citizens, and a Nigerien (Niger) citizen as well, have been handed over to the ICRC."
"We will hand them over to the Niger authorities. If everything goes well it will happen tomorrow," he added.
He could give no further details about the Niger national.
The rebel movement has taken dozens of Niger army soldiers hostage during more than a year of inconclusive on-off fighting that has killed at least 200 rebels and 70 government troops.
The four French hostages were employed at Areva's Cominak mine at Arlit in northern Niger.