´óÏó´«Ã½

The United States Coast Guard says an oil spill that has caused a huge slick in the Gulf of Mexico is far worse than previously thought, threatening a major ecological disaster.

Officials said up to 5,000 barrels of oil were pouring into the sea every day, five times more than had been estimated.

The leak began last week after a drilling rig exploded and sank.

Newshour's Claire Bolderson looks in depth at the crisis, with contributions from:

• Mike Miller, head of Canadian oil-well fire-fighting company, Safety Boss

• Jacqueline Savitz, a spokeswoman for the marine conservation group, Oceana

• Ray Brandhurst, a shrimp fisherman in Slidell, Louisiana

• David Cohen, News Director of WWL, a news, talk and sports radio station in New Orleans

• Dr Simon Boxhall, an expert in marine pollution and oil spills at the University of Southampton

First broadcast 29 April 2010