Oil pollution from the spill
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US govt: 'No premature celebration' on BP oil seal

BP says that the first phase of a procedure to permanently seal its underwater well in the Gulf of Mexico has been a success.

The process, known as a 'static kill', involves forcing a mixture of mud and concrete into the blown-out well to permanently seal it.

Speaking on Tuesday, US government's oil-spill response chief Thad Allen welcomed reports the seal was working, but warned against "premature celebration", adding there was still much clear-up work to do.

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