Gulf leak eclipses Exxon Valdez as worst US spill

This early Thursday morning, May 27, 2010 image made from video released by British Petroleum (BP PLC) shows equipment being used to try and plug a gushing oil well in the Gulf of Mexico. BP started pumping heavy mud into the leaking Gulf of Mexico well Wednesday and said everything was going as planned in the company's boldest attempt yet to plug the gusher that has spewed millions of gallons of oil over the last five weeks. (AP Photo/BP PLC) (AP Photo/BP PLC)

May 27, 2010 7:04:29 PM PDT
As BP labored for a second day Thursday to choke off the leak at the bottom of the Gulf of Mexico, dire new government estimates showed the disaster has easily eclipsed the Exxon Valdez as the biggest oil spill in U.S. history.