U.S. officials say the BP-leased Deepwater Horizon oil well -- which spilled an estimated 4.9 million barrels into the Gulf of Mexico since April -- has been secured and no longer constitutes "a threat."
The announcement by Admiral Thad Allen, the U.S. official overseeing the response to the oil spill, comes after crews removed a damaged valve known as a "blow-out preventer" and placed a new device over the well on September 3.
The damaged 300-ton valve was raised to the surface overnight and secured aboard a boat -- allowing investigators to get a close look at what caused the accident.
Meanwhile, a relief well is expected to be completed in mid-September, allowing BP to permanently seal the blown-out well.
compiled from agency reports