Britons freed from hijacked Nigerian oil rig

Five British oilmen are among 100 workers freed on Monday after being held hostage for four days off the coast of Nigeria, the Foreign Office said. A spokeswoman said the hostages had been aboard a rig that drills for Shell, four miles offshore from Warri, southern Nigeria, and which was taken over "by a group of youths" last Thursday night.

"The five British nationals are unharmed and we have been in touch to offer them consular assistance," she said. The freed workers were taken to the mainland by helicopter last night.

Protesters in southern Nigeria regularly take hostages from oil companies, and sabotage pipelines to call attention to their poor living conditions. Nigeria's crude oil ranks among the purest grades and the country is the world's seventh largest oil producer, bringing in $20bn (£13.8bn) a year in revenues. There are said to be 22.5bn barrels of oil in reserve.

But poverty-stricken villagers in southern Nigeria say they are suffering from pollution caused by oil exploration and they struggle to survive. They are rarely given skilled jobs by the oil companies. Their plight was starkly illustrated by protests in the mid-Nineties, led by the writer Ken Saro Wiwa and his Ogoni ethnic group. Saro Wiwa and eight other activists were executed in 1995 by Nigeria's late dictator, General Sani Abacha.

Much of the corruption that has blighted Nigeria for decades stems from its oil wealth. With the complicity of multinational oil companies, successive military regimes stuffed their pockets with proceeds from oil licences without passing on gains to the people.

In 1999, a civilian government was put in. It pledged to stamp out the corrupt practices of oil multinationals and to demand stringent adherence to ecological standards. Since then, youth groups have started kidnapping oil workers for ransom. Two years ago, more than 20 Britons were taken by militant groups in the Niger Delta. Last August, five Britons were held on rigs in the southeastern state of Bayelsa. Both hostage groups were freed unharmed.

The Trident rig from which yesterday's hostages were freed is understood to belong to Transocean Sedco Forex, a company based in Houston, Texas, which is a drilling operator for a range of multinationals. Apart from the Britons, there were five Americans, three Australians, one South African and one Trinidadian. Cerris Tavinor, a Shell spokeswoman in London, said the youths involved in the Trident hostage-taking came from the Bilabiri community in south-east Bayelsa state. It is not known if they were armed. Earlier this month, a group of militants held hostage 165 oil workers for four days on two other Shell rigs in Nigeria.

¿ Up to 70 people may have died when a tyre burst on their bus and it swerved and plunged into a river in Ciromawa district, northern Nigeria on Sunday, rescue workers said. The bus had been travelling from the commercial capital of Lagos to Kano.

By last night, 15 bodies had been recovered but rescue workers said they feared up to 46 more were inside the vehicle and some may have been swept away by the currents. Divers have been called in.