The Nigerian military says it has recovered the body of a military officer kidnapped earlier this week in the country's volatile Niger Delta region.
Officials with a joint military task force in the region say the officer, a lieutenant, was abducted during a raid by armed militants in Rivers state on Sunday.
No one has claimed responsibility for the attack.
Meanwhile, gunmen continue to hold nine South Korean workers kidnapped Wednesday near Yenagoa, the capital of Bayelsa state. South Korea's government says it has started talks with the hostage-takers.
Attacks and kidnappings are common in the oil-rich delta region. Militants have been pressing the Nigerian government to give impoverished local communities more of the region's oil revenue.
The attacks have cut Nigeria's oil production by around 20 percent since last February. Under normal conditions, the country pumps about 2.5 million barrels of oil a day.
Some information for this report was provided by AFP and Reuters.