The Deepwater Horizon oil spill was a major industrial accident on the Gulf of Mexico, which killed 11 people and injured 16 others, leaked about 4.9 million barrels (210 million US gal; 780,000 m3) of oil with plus or minus 10% uncertainty,[140] which makes it the largest accidental marine oil spill in the history of the petroleum industry,[141][142] and cost to the company more than $65 billion of cleanup costs, charges and penalties.[143][144] On 20 April 2010, the semi-submersible exploratory offshore drilling rig Deepwater Horizon located in the Macondo Prospect in the Gulf of Mexico exploded after a blowout. After burning for two days, the rig sank.