A well on the North Slope of Alaska owned by oil and gas company BP was no longer spraying crude oil but was still emitting natural gas, the Alaska Department of Environmental Conservation (ADEC) said. Fox News is reporting there are actually two leaks - one near the top and one further down the well assembly, says BP.
BP did not have an estimate available for the volume of oil and natural gas spilled.
"Crews are on the scene and are developing plans to bring the well under control, " said Brett Clanton, a BP spokesman, "and safety will remain our top priority as we move through this process".
The Alaska Department of Environmental Conservation says the spill is ongoing and the volume is unknown.
The leak was discovered Friday morning, with natural gas spewing out of the well and a "spray" of crude oil landing on the snow-covered drilling-well pad. The gas, which comes up along with oil, is typically pumped back underground to squeeze more crude oil out of the reservoirs.More news: French Socialist candidate holding Paris rally
"Responders determined that the well had 'jacked up, ' or risen, approximately 3 - 4 feet; this vertical movement of the well caused the pressure gauge to break off and prevented operations from pumping into the well to kill it", ADEC reported. BP was fined $255 million by the state of Alaska for negligence in their maintenance of Prudhoe Bay pipelines. This last March, daily output in the area hit 565,000 bpd - the highest in more than three years.
It is still unclear, how much oil has spilled.
Employees on Friday morning discovered leaks at the oil and gas well in the Alaskan Arctic about five miles from the remote town of Deadhorse. In 2006, a BP well in Prudhoe Bay spilled about 267,000 gallons of oil, the largest in the region's history.
The agency says the initial oil release may have affected an area of about one hectare and there were no reports of damage to wildlife.