Nigeria's military forces say they have found two Russian hostages abducted in the Niger Delta two months ago, who managed to break free.
The two abductees escaped from their captors and wandered in the Delta for several days before being spotted by Nigerian troops, a spokesman said.
Two Russian employees of UC Rusal at the Alscon aluminium smelter were snatched in Ikot Abasi on 20 December.
They were reportedly taken by gunmen in speedboats in the middle of the night.
Lt Col Sagir Musa, a spokesman for the Nigerian military, said the Russians had managed to slip away from their kidnappers.
"[They] escaped from a yet to be identified military camp and for the past five days were wandering in the creeks before our own patrol team saw and rescued them," he added.
More than 200 foreigners have been kidnapped by militants in the Niger Delta, the heart of the country's oil industry, since 2006.
A collapse in law and order has allowed armed groups to make a living extorting money from oil companies that have to keep their operations going, correspondents say.