Alaska hit by 'massive' oil spill: "An oil spill discovered at Prudhoe Bay field is the largest ever on Alaska's North Slope region, US officials say.

They estimate that up to 267,000 gallons (one million litres) of crude leaked from a corroded transit pipeline at the state's northern tip.

The spill was detected on 2 March and plugged. Local environmentalists have described it as 'a catastrophe'.

In 1989, the Exxon Valdez shipping disaster spilled 11m gallons (42m litres) of oil onto the Alaskan coast.

'Painful reminder'

'I can confirm it's the largest spill of crude oil on the North Slope that we have record of,' Linda Giguere, from Alaska's state department of environmental conservation, was quoted as saying by the Associated Press news agency.

The estimate is based on a survey conducted several days ago at the site where the leak was discovered, officials say.

The spill covers about two acres (one hectare) of the snow-covered tundra in the sparsely populated region on Alaska's north coast, some 1,040km (650 miles) north of the state's biggest city, Anchorage.

The source of the spill was a hole caused by internal corrosion in the pipeline, officials say. It remains unclear when the leak started.

Environmentalists from Alaska Wilderness League said the spill was 'a catastrophe for the environment'.

They said"