Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. BP: Multiple Companies to Blame for Gulf Oil Spill VOA News 08 September 2010 In this 21 Apr 2010 file aerial photo, the Deepwater Horizon oil rig is seen burning Photo: AP In this 21 Apr 2010 file aerial photo, the Deepwater Horizon oil rig is seen burning British oil giant BP says multiple companies and work teams were responsible for the oil spill disaster in the Gulf of Mexico. In an internal report released Wednesday, BP said the accident was the result of a complex series of mechanical failures, human judgments and engineering design. Outgoing BP chief executive Tony Hayward said his company as well as partners Halliburton and Transocean were all involved in the disaster. The report is the result of a four-month investigation led by BP's head of safety and operations. The report proposes 25 recommendations to help prevent a similar disaster, and BP says the guidelines could be applied industry-wide. The April 20 oil rig explosion killed 11 workers and released millions of barrels of oil into the Gulf. The report will not be the only account of the disaster, as the U.S. Justice Department and other government panels continue their investigations. .