It was unusual even by standards in Montana, where black bears have to be euthanized every so often after incidents with humans: 7 bears, including 2 cubs, had to be put down over the last week because an individual had been feeding them and many others -- reportedly for years.

"The last thing we wanted to do is remove these bears," Lee Anderson, a warden with Montana Fish, Wildlife & Parks, said in a statement Wednesday by the agency after five bears were killed in recent days. "But we had no choice because of the danger they pose to local residents."

Two more were found and euthanized later Wednesday.

"This was very unusual," spokesman John Fraley told NBC News. "I can’t remember this many bears euthanized in such a short period of time in the past decade or more in our area."

The agency responded after getting reports that a resident of Heron, a town close to the border with Idaho, was feeding bears.

"One male black bear weighed 485 pounds, and one female weighed nearly 300 pounds," the agency stated. "These are unusually heavy for black bears, reflecting their condition in response to artificial feeding."

A woman told the local newspaper, the Sanders County Ledger, that she had been feeding the bears, many of them orphans, as a way of "teaching them to survive in the wild."

"I taught them to run from outfitters and pickups," said Barbara Sweeney, who added that she and her late husband had run an animal refuge at their property for 22 years.

"I taught them how to hibernate, too," she said. 

"People have known I've been doing this for years" and without any problems, she added. "If they would have said something, I would have stopped."

The case is under investigation, and the local county attorney could press charges. Montana law bars the feeding of bears and other wildlife.

Montana does allow seasonal hunting of black bears, which are not an endangered species.

The department said it could not find a zoo willing to take the bears and that releasing them somewhere else could pose new problems.

"It would be irresponsible to release these potentially dangerous bears somewhere else when the bears are in such a food-conditioned state," said Department Wildlife Manager Jim Williams.

Such bears have a history of attacking humans, including an attack in late September in Montana's Bob Marshall Wilderness Area, he added.

"This is a very unfortunate example of how feeding bears directly leads to their death," noted Jim Satterfield, supervisor for the area where the bears were fed. "This is why we tell the public that feeding a bear is the same as signing its death warrant."

The euthanized bears were buried in a landfill to prevent contact with humans or wildlife, the agency said.

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