The kidnapping of seven foreign oil workers on early Wednesday from an Italian supply vessel some 50 km off the coast of southern Nigeria ended with one hostage killed and another one seriously wounded, a Nigerian military source said on Wednesday.

In a rescue operation launched by the Nigerian army, a British hostage was killed and an Italian hostage was gravely wounded while the other five were freed without hurt, said the military officer who refused to be identified.

He added that two kidnappers and one government soldier were also dead, but stressed that the rescue mission was fairly successful.

"During the attempt by Nigerian military marines to free the seven hostages ... gunfire was exchanged during which a hostage was killed while six others, one of whom was wounded, were freed and are safe," the Italian company ENI said on its website.

British Foreign Ministry also confirmed the hostage killed was a British national. According to the ENI, the parent company of the Agip company which owned the supply vessel, the kidnapped foreigners included one Italian, one Briton, a Filipino, two Finns, a Pole and a Romanian.

The seven foreigners were captured on the Agip's supply vessel off the Nigerian coast, about 50 km from the coast of Nigeria's southern state of Cross Rivers.

Joshua Benamiasia, coordinator of the Bayelsa State Government security outfit "Bayelsa Volunteers," said information reaching him had it that the navy had intercepted the militants.

So far no group has claimed responsibility for the kidnapping, but a reliable source said the rampaging militants that invaded the Clough Creek flow station at Ekeremor and the Tebidaba flow station may have been responsible for the latest attack following the alleged refusal of the state government to pay them the usual ransom as was claimed to be the practice in the past but often denied by the latter.

In Lagos, Nigerian police, who had confirmed the kidnapping, denied all knowledge of the rescue attempt or of casualties.

The kidnapping was the latest in a series of attack on oil installations in the volatile Niger Delta, where most of the country's oil is produced. Since the beginning of the year, militant groups have constantly attacked oil facilities and taken oil workers hostage.

Nigeria, Africa's largest oil producer and the sixth largest oil exporter in the world, has a daily crude oil output of 2.6 million barrels.

(Xinhua News Agency November 23, 2006)