The Nigerian navy says 12 foreign sailors seized in the volatile Niger Delta two days ago have been released.
Navy spokesman David Nabaida told reporters Sunday that the 12 men were put on a fishing trawler and taken into the navy's care.
Unidentified gunmen kidnapped the sailors late Friday after attacking a German cargo ship, the BBC Polonia, off the Niger Delta coast. One crew member was shot during the incident.
The captured sailors included men from Germany, Lithuania, Russia, and Ukraine.
The Niger Delta is Nigeria's oil-producing region. Local militants have carried out numerous attacks on the oil industry since late 2005, while demanding that residents get a larger slice of oil revenue.
Attacks and kidnappings by the militants have cut Nigeria's oil production.
Nigerian President Goodluck Jonathan has said he will revive an amnesty program for the militants introduced by his late predecessor, Umaru Yar'Adua.
Thousands of militants handed in their weapons last year as part of the program. The militants were promised education and jobs, but the process stalled when Mr. Yar'Adua fell ill in November. He died in May.