Voters of a small southwest Alaska borough late Monday narrowly passed a measure blocking a proposed gold and copper mine that critics say would have threatened one of the world's premier wild salmon fisheries in a local election that gained national attention, pitting environmentalists against business interests in a bitter feud.

The vote bans large-scale resource extraction, including mining, that would destroy or degrade salmon habitat. The measure was aimed squarely at Pebble Mine, a massive gold and copper prospect near the headwaters of Bristol Bay.

The debate surrounding Pebble has attracted the attention of chefs, actor-director Robert Redford and big-name jewelers who have vowed not to sell any gold coming from the operation. Their concerns support local opponents who fear the mine would fundamentally change the area's landscape and disrupt, if not destroy, a way of life.

Supporters of the Pebble project, which has been described as potentially the world's largest man-made excavation, have said that it could create up to 1,000 long-term jobs in economically-depressed rural Alaska and that the project can be "done safely to co-exist with clean water, healthy fisheries and traditional ways of life."

Unofficial results, released by the Lake and Peninsula Borough clerk late Monday, showed 280 in favor of the measure and 246 against.

The proposal was the subject of an intense public fight, and the vote is unlikely to be the last word on whether, or how, the mine is built _ a court challenge has already been filed.

Pebble Limited Partnership has argued, in part, that the measure would improperly bypass the role of the local planning commission. The office of Alaska's attorney general has said the initiative would enact an ordinance that is "unenforceable as a matter of law."

A judge has put the case on hold until Nov. 7.

Pebble spokesman Mike Heatwole said the company would press ahead with its plans, in spite of the vote and passage of what he said company officials believe to be an illegal law.

Voters were "subjected to a prolonged advertising campaign of fear-mongering and misinformation about the Pebble project," he said in a statement. "We believe this has done a disservice to the people of Southwest Alaska and we will continue our efforts to share our perspective that Pebble can be done safely to co-exist with clean water, healthy fisheries and traditional ways of life, while generating decades of economic and social benefits for the people of the region."

The mine is a joint venture of Canada-based Northern Dynasty Minerals Ltd. and Anglo American plc of the United Kingdom.

The companies have spent hundreds of millions of dollars scoping out the deposit, which Northern Dynasty has described as the largest undeveloped deposit of its type in the world, with the potential of producing 53 billion pounds (24 billion kilograms) of copper, 50 million ounces (1.4 billion grams) of gold and 2.8 billion pounds (1.27 billion kilograms) of molybdenum over nearly 80 years.

The mine would be directly above Iliamna Lake, the largest producer of sockeye salmon in the world.

This year, the commercial harvest of Bristol Bay salmon was valued at nearly $138 million, which doesn't include fish caught by Alaska Natives for subsistence. The Bristol Bay Native Corp., which has more than 8,000 shareholders with ties to the region, also is opposed to the mine, which would be located 200 miles southwest of Anchorage.

Critics say the potential footprint of the project could cover 15 square miles, with an open pit and network of roads and power lines. But project officials counter that neither a pre-feasibility study nor a formal mine plan have been completed.

Jackie Hobson, a supporter of the so-called Save Our Salmon Initiative, said the results "prove once and for all that Native Alaskans will not allow important salmon habitat to be destroyed for the sake of enriching foreign corporations."

The proposed mine has attracted worldwide attention. Redford has blogged about it, and spoke out against the mine in an ad in the New York Times.

More than 200 chefs from around the country have sent a letter to the U.S. Environmental Protection Agency protesting the mine.

And some of the nation's leading jewelers, including Zale Corp., Tiffany & Co., Helzberg Diamonds and Ben Bridge, have pledged to support the "No Dirty Gold" campaign and not purchase precious minerals from Pebble Mine.

The election was conducted by mail, with ballots having to be postmarked by Oct. 4. Officials in the borough of about 1,600 people counted them by hand Monday.