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A BP well located on Alaska's North Slope is no longer leaking crude oil or natural gas, a company spokeswoman said Monday.

The crude spray was discovered Friday morning, and capped early Sunday. A second leak at the well that was emitting gas at a reduced rate was closed off overnight on Sunday, according to spokeswoman Dawn Patience in an email on Monday.

The leak came as the remote North Slope, once home to America's biggest oilfields, has seen signs of a resurgence as producers work to boost output from aging wells and extend their reach to new supplies.

Production there rose to 565,000 barrels a day in March, its highest level since December 2013. That's still down by almost three-quarters from the peak of more than 2 million barrels in the late 1980s.

"The well is no longer leaking any gas or oil," Patience wrote. "Overnight, the Unified Command achieved source control and killed the well. "

In 2010, a BP well became the site of the worst offshore oil spill in U.S. history. The deadly Deepwater Horizon accident in the Gulf of Mexico forced BP to sell billions of dollars in assets and set aside more than $50 billion to pay for damages.

The volume of the North Slope leak hasn't been determined and the cause of the release is unknown, the state's Department of Environmental Conservation has said. There have been no injuries and no reports of harm to wildlife. The nearest local community, Nuiqsut, located about 50 miles west, has been notified

"It's tough to determine collateral impacts at this point, but some incident-related slowdown at Prudhoe Bay seems at least a reasonable risk to consider," Tudor Pickering Holt & Co., a Houston-based energy investment bank, wrote in a Monday note.

Based on aerial pictures, the release appeared to be contained to the gravel pad surrounding the well head and never reached the surrounding tundra, BP said in an earlier statement. The well has been shut in since Friday.

Alyeska Pipeline Service Co.'s Trans-Alaska Pipeline System, which runs from Prudhoe Bay south to Valdez, isn't affected by this incident and is operating normally, Michelle Egan, a company spokeswoman, said by telephone Sunday.

Alyeska is a joint partnership led by the North Slope's top producers, BP, ExxonMobil and ConocoPhillips.

Alaskan North Slope crude was valued at $1.80 a barrel over U.S. benchmark West Texas Intermediate on Monday, according to data compiled by Bloomberg. It has averaged a $1.16 premium to WTI this year.