* April 20: At around 10 p.m. a fire is reported on the central time on the Deepwater Horizon rig, owned by Transocean Ltd. and under lease to energy giant BP, according to an April 21 [statement ](http://www.bp.com/genericarticle.do?categoryId=2012968&contentId=7061443)from Transocean. There is no mention of any possible spill. Eleven workers are killed.
* April 22: With the media coverage of the explosion focusing on the missing workers and, initially, not about the possibility of a spill, AFP notes the possibility of an environmental disaster: the rig had been drilling 8,000 barrels of oil per day, and had 700,000 gallons of diesel fuel on board. "Worst case scenario, there is a potential environmental threat," Coast Guard spokeswoman Katherine McNamara tells the wire service.
BP's chief executive, Tony Hayward, [says](http://www.bp.com/genericarticle.do?categoryId=2012968&contentId=7061490) BP will do "everything in our power to contain this oil spill and resolve the situation as rapidly, safely and effectively as possible." The company said it dispatched a team to deal with the oil that dispersed from the original blast.
* April 23: The day after the rig sank, the AP [reports](http://www.latimes.com/news/nationworld/nation/la-na-oil-rig-explosion-20100424,0,1804008.story): "Coast Guard Rear Adm. Mary Landry said Friday morning that no oil appeared to be leaking from the well head at the ocean floor, nor was any leaking at the water's surface. However, Landry said crews were closely monitoring the rig for any more crude that might spill out.
* April 24: In the late afternoon, the AP [reports ](http://www.breitbart.com/article.php?id=D9F9M8V00&show_article=1)that the Coast Guard has reversed its earlier statement that there was no oil leaking. The wire service quotes Guard officials as saying an estimated 1,000 barrels of oil per day are coming out of the well head on the ocean floor, 5,000 feet under water. Landry says that the oil may have been pouring out since the rig sank on April 22.
BP's chief operating officer, Doug Suttles, speaking about options on responding to the spill, [says](http://www.kansascity.com/2010/04/24/1899544/rain-choppy-seas-halt-cleanup.html), "Over the next several days, we should determine which method is the best one to follow"
* April 26: BP says in a [press release](http://www.bp.com/genericarticle.do?categoryId=2012968&contentId=7061537) it is 'accelerating offshore oil recovery and continuing well control efforts. Improved weather "combined with the light, thin oil we are dealing with has further increased our confidence that we can tackle this spill offshore," says BP chief exec Tony Hayward.
* April 27: After underwater robots fail to stop the flow of oil, the coast guard [floats ](http://www.kboi2.com/news/national/92232314.html)the idea of containing pools of oil in containment booms and then setting it on fire.
Meanwhile, BP says it will begin drilling a new relief well near the spill site later in the week; the process could take months.
Rep. Henry Waxman (D-CA), chair of the Energy and Commerce committee, writes a [letter ](http://energycommerce.house.gov/Press_111/20100427/McKay.BPAmerican.pdf) (.pdf) to the chairman of BP notifying him of an investigation into "what the companies knew about the risks of drilling at the site and the adequacy of the companies' response plans." He charges that "[a] striking feature of the incident is the apparent lack of an adequate plan to contain the spreading environmental damage. The two companies involved, BP Exploration and Production, Inc., and Transocean Ltd., are attempting to contain the oil spilling from the well with techniques that have never been used before at these ocean depths."
Homeland Security Secretary Janet Napolitano and Interior Secretary Ken Salazar [announce ](http://news.yahoo.com/s/ap/20100427/ap_on_bi_ge/us_oil_rig_explosion_investigation)an investigation of the explosion.
* April 28: Late Wednesday, the Coast Guard announces that 5,000, not 1,000, barrels a day of oil are spilling, citing a new National Oceanic Atmospheric Administration estimate.
At the same press conference as the Coast Guard announcement, BP COO Doug Suttle disputes the new estimate and argues that a newly discovered leak does not change the rate of the spill. "He showed a diagram showing where the leaks are and said the newly discovered leak is upstream from the previous leaks," the AP [reports](http://abcnews.go.com/Business/wireStory?id=10499674).
* April 29: Suttle [acknowledges ](http://www.google.com/hostednews/ap/article/ALeqM5g5gnWbqZ9SqBHvSYqJeE2AT5KebwD9FCULD80)on the Today Show that the government's new estimate may be accurate.
In a Rose Garden statement, Obama [says ](http://news.yahoo.com/s/ap/20100429/ap_on_bi_ge/us_oil_spill_obama)the Administration will use "every single available resource" to address the spill, including the military. He also says BP will have to pay the costs.