Gunmen on Tuesday released 24 Filipino sailors taken hostage in Nigeria's lawless southern oil-producing region, which has been roiled by weeks of stepped-up violence and kidnappings, officials said.

Sheddy Ozoene, a spokesman for Delta State government, said the Filipinos were aboard the ship from which they were taken Jan. 20 and that the freed sailors were heading to the southern port city of Warri.

"We understand that they were released onto the ship this morning," he said, adding that the men were being accompanied by local government officials.

Officials of the German-based shipping company couldn't confirm the release.

Baco-Liner Managing Director Klaus Steffen told The Associated Press that he could not give details of ongoing negotiations, saying that he did not want to jeopardize anything.

"Everything is progressing," he said in a telephone call from his company headquarters in Duisburg, Germany.

Militants and copycat criminals have carried out a string of bombings and kidnappings of foreigners over the past year, violence that has cut crude production in Africa's biggest oil exporter by nearly a quarter.

Over the past month, strife has increased with more than 60 kidnappings since the beginning of the year — most of them unrelated to the oil industry.

Seven foreigners, including one woman, remain in captivity.

The militants claim to be fighting for a more equitable distribution of oil revenues to fund development in the impoverished Niger Delta region. Most of the recent kidnappings appear to be non-political and carried out by people seeking ransom.

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