Nebraska officials voted on Wednesday to revoke the liquor licenses of four stores in the tiny town of Whiteclay, potentially cutting off a major source of alcohol to Native Americans who live a short walk away on the dry Pine Ridge Reservation.

The state liquor board said that the town was not adequately served by law enforcement, sufficient cause to deny the renewal of the licenses.

The decision was applauded by legislators and activists who had pressured the state for years to close down the stores, arguing that they were encouraging alcohol consumption among people who historically have high rates of alcohol abuse and fetal alcohol syndrome.

But the store owners immediately vowed to appeal, a move that could keep the stores open while a battle takes place in the courts.

The fate of the liquor stores was closely watched in Nebraska and South Dakota, where residents have long debated their legitimacy and their effect on the Pine Ridge reservation, their neighbor to the immediate north.

Whiteclay, a town with only a dozen residents surrounded by ranching country, is several hundred feet from the South Dakota border, and easily accessible to Native Americans who live on the reservation. Many people walk into Whiteclay every day, drink openly on the streets and sleep there at night. Police are frequently called to the town to assist intoxicated people or break up fights.

But supporters of the stores say closing them might only spread the problem further, encouraging people to drive further to seek alcohol.

Andrew Snyder, a lawyer for the stores, said in an email that the commission’s decision defied Nebraska law. He said the commission was evaluating the stores based on rules appropriate for new applicants for liquor licenses, not for those seeking renewals for their longstanding places of business. “The decision has confirmed what we have known all along, this is politically motivated with pressure directly from the governor’s office,” Mr. Snyder said.

Gov. Pete Ricketts of Nebraska has vowed to address the situation in Whiteclay, but has not taken a public stance on the stores’ licenses.

Last year, the three-member Nebraska Liquor Control Commission ordered the stores, for the first time in years, to reapply for their liquor licenses, which will expire on April 30. Earlier this month, during 10 hours of hearings in Lincoln, officials in Sheridan County insisted that there was adequate law enforcement for the stores, a condition required for them to keep their licenses.

The store owners are facing a separate threat from the state attorney general in Nebraska, who says they have engaged in illegal alcohol sales to bootleggers. A hearing on those potential violations is expected to take place in June.

On Wednesday, the commission members appeared unconvinced that Whiteclay has received sufficient attention from law enforcement officials in Sheridan County. Speaking in a small, packed hearing room, the members of the commission said they were moved by testimony they heard this month, accounts of public intoxication, fighting and sexual assault.

Robert Batt, the chairman of the commission, emphasized that the commission was enforcing the laws of the state. “We’ve had a lot of complicated problems come before us, none more complicated than this,” he said. “The real underlying issue here, legally, is that we did this by the book, used due process.”

“This was done after a lot of deliberation,” he said, “a lot of heartache.”

The commission then voted unanimously to revoke the licenses, prompting many in the hearing room to burst into applause.

Bruce BonFleur, a Whiteclay resident who runs a ministry there with his wife, Marsha, cheered the decision.

“I think the Nebraska liquor commission acted in a precise and thorough manner and concluded the obvious — that there is not adequate law enforcement in Whiteclay,” he said. “We look at this decision as an initial and vital early step in what will be a transformed Whiteclay, one that promotes life, healing and hope.”