Robot vessels used to cap Gulf of Mexico oil leak

Robotic submersibles are being used to try to stop a fast-flowing oil leak nearly a mile (1.5km) below the surface in the Gulf of Mexico.

Some 1,000 barrels (42,000 gallons) of oil a day are spewing from a damaged well, after a drilling rig exploded and sank off the Louisiana coast last week.

British oil company BP, which leased the rig, said the "first-of-its-kind" attempt would take 24 to 36 hours.

There are fears of an environmental disaster if the mission fails.

Conservation experts say the oil leak has the potential to damage beaches, barrier islands and wetlands across the coastline.

For now, the weather conditions are keeping the oil away from the coastline and it is hoped the waves will break up the heavy crude oil, allowing it to harden and sink back to the ocean floor.

'Very serious'

BP is using submersible vehicles, equipped with cameras and remote-controlled arms, to try to activate a blow-out preventer - a series of pipes and valves that could stop the leak.