Three Western oil workers, including two Americans and a Briton, held in Nigeria's troubled oil-rich Niger Delta by militants for more than one month, have been released, a state government spokesman said on Monday.

"They were released to the state government at about 3:20 a.m. (0220 GMT) this morning," Abel Oshevire, the Delta State spokesman told Xinhua by telephone. "They are all in good health and with ( Royal Dutch) Shell officials, their employer."

He said the government had assured the Ijaw militants belonging to Movement for the Emancipation of the Niger Delta (MEND) that they would not be attacked by the Nigerian army after the release.

The MEND is not immediately available for comments. On Saturday, the group in an e-mail statement reiterated threats of more hostage-takings in the delta, the oil industry heartland in Africa 's biggest oil exporter.

"In response to the Nigerian governments demand for an unconditional release of the hostages, our units have been directed to capture more expatriates across the Niger Delta," they said at that time.

The three hostages were seized along with six others on February 18 from a vessel laying a pipeline for Shell by the militants in retaliation for military bombardment of their strongholds on the ground of rooting out oil thieves. The six others, however, were later released.

Originally, the militants were insisting on the demilitarization of the delta as a condition for the release. They also vowed not to compromise on its demands for the release of two ethnic Ijaw leaders, payment of 1.5-billion-U.S. dollar compensation to Ijaw communities affected by Shell spillages.

Nigeria's oil output has been cut by about 630,000 barrels per day, or a quarter, after four-month attacks on oil facilities by the militants led by the MEND in the delta, where about 20 million locals live in abject poverty despite its huge oil wealth.

Source: Xinhua