Gunmen seized four more foreign workers amid a dramatic rise in violence that has rocked Nigeria’s southern petroleum-producing region, oil industry officials said today.

Militants in restive southern Nigeria today claimed to have bombed three major oil pipelines.

Eight foreign hostages seized by gunmen from an offshore vessel in southern Nigeria today have been released, the militant group that organised the kidnappings said.

Militants seeking a greater share of oil revenue for their impoverished region detonated two car bombs in Port Harcourt, Nigeria, sending shock waves through the city.

Militants in Nigeria are planning a major new wave of attacks and kidnappings in the next few days that could include up to 20 simultaneous bombings across the country’s oil-rich delta region, US diplomats warned today.

Armed militants in Nigeria vowed yesterday to cut daily oil exports from this West African nation’s troubled delta region by another one million barrels by the end of March, as OPEC nations prepared for a strategy meeting in Vienna this week.

Officials in an oil-rich southern Nigeria state where militants took nine foreigners hostage, including a British man, were today investigating conflicting reports that three of the captives had been released on medical grounds.

Militants who kidnapped nine foreign oil workers and forced a 20% cut in Nigerian crude exports yesterday vowed to escalate the violence, threatening for the first time to fire rockets at international oil tankers. The military said tankers in Nigerian waters were safe.

Royal Dutch Shell shut down an oil facility pumping 37,800 barrels of crude a day in Nigeria’s southern oil-rich delta, following a blaze at a nearby oil well, the company said.

The leader of Nigerian militants who captured four foreign oil workers said today he would not talk with negotiators sent by the government and reiterated threats to launch new attacks on oil installations.

NIGERIAN kidnappers have said their American hostage is gravely ill and threatened to kill three other foreign oil workers held captive if he died.