Four kidnapped Lebanese workers of a construction company in southern Nigeria have been released by their abductors, a local police spokesperson told Xinhua on Saturday.

The Lebanese were kidnapped by gunmen dressed like soldiers on May 14 in the oil-rich Delta region.

The southeast Akwa Ibom State police spokesman Gabriel Ngban said the expatriates were in a stable condition when they were released.

"Yes, they have been released, we are putting our report together," he added.

Ngban said he did not know if any ransom was paid.

The state commissioner for police Walter Rugbere also confirmed the release to Xinhua on phone.

"I have been informed about their release. I have sent my men to them, and personally I am on my way to see them," he added.

A source at the Lebanon Embassy in Abuja also confirmed the release but decline to provide more details.

The oil-rich Niger Delta has been restive for years with militants attacking both foreign oil facilities and workers.

Over 300 foreigners have been seized in the Niger Delta since 2006. Almost all have been released unharmed after paying a ransom.