Photo timeline of Gulf oil spill (54 images)

A thorough investigation will determine if criminal charges should be filed in the Gulf of Mexico oil spill, U.S. President Obama said on June 1. The president met with the two men he has appointed to lead the inquiry, former U.S. Sen. Bob Graham, D-Fla., and former Environmental Protection Administration head William K. Reilly. "If laws were broken, leading to death and destruction, my solemn pledge is, we will bring those responsible to justice," Obama said at the White House. (UPI/Kevin Dietsch)

Work boats pull booms to skim oil at the site of the BP Deepwater Horizon oil leak in the Gulf of Mexico May 29, 2010. BP admitted that its "top kill" operation had failed to plug the well, and the company is proceeding with other efforts to stop the leak. Remotely operated vehicles are preparing to install a lower marine riser package cap containment system at the site of the leak. Following these preparations, BP said it will connect a containment cap to a drill ship and begin capturing "most" of the leaking oil and natural gas. (UPI/A.J. Sisco)

BP stock plunged as much as 17 percent, wiping out almost $18 billion of market value after the "Top Kill" method failed to stop up the flow of oil. (UPI/Alexis C. Glenn)

BP announce that the "Top Kill" process, which attempted to seal the leak with mud and cement, failed. Officials said it may now take months to fully seal the leak, which has already devastated the Gulf Coast. UPI/BP