Oil rig explosion

NEW ORLEANS, May 4 (UPI) -- The oil company that operated an offshore drilling platform that sank and set off a potential environmental disaster said work on a relief well at the site has begun.

BP issued a statement Tuesday saying a relief well was being drilled, with a plan to have the new well cut off the flow of oil to a wellhead from which 5,000 barrels of crude oil a day is leaking.

BP operated the Deepwater Horizon platform in the Gulf of Mexico on which an explosion occurred April 20, causing a huge fire and the deaths of 11 workers. The platform sank two days later and it was soon obvious the wellhead on the floor of the gulf -- about a mile below the surface -- was leaking oil. That created a huge sheen on the surface and oil has reached the Louisiana coast some 50 miles away.

The oil company is using a multipronged attack to stem the flow. Robotic submarines were dispatched to try to shut the flow while containment domes, meant to be placed over the damaged wellhead, were manufactured and the relief well drilling was begun Sunday.

"This is another key step in our work to permanently stop the loss of oil from the well," BP Group Chief Executive Tony Hayward said in the release. "At the same time we are continuing with our efforts to stop the leak and control the oil at the seabed, to tackle the oil offshore, and to protect the shoreline through a massive effort together with government agencies and local communities."