A brown bear sow was found dead in the woods near a popular fishing hole on the Russian River on Tuesday afternoon, possibly dying after it had been gut shot two days earlier, according to state and federal officials.

The shooting was never reported to the state Department of Fish and Game as required by law, and it orphaned the bear's three 2-year-old cubs.

"It appears as if a grizzly bear has been killed for the wrong reasons and left to rot," said Jim Hall, deputy manager of the Kenai National Wildlife Refuge. "And, as a result of someone's irresponsible action, or what appears to be irresponsible actions at this point in time, other people were put in danger."

The cubs, each about the size of an adult black bear, charged a federal officer at the scene. Later in the evening, one of the cubs "drove" about 35 anglers down the Kenai River bank, prompting a temporary closure of the ferry across the river on Tuesday night, Hall said.

The killing "was a terrible thing," said Russian River Campground host Butch Bishop. "This was a sow with three cubs. ... They had really bad habits, but mom kept them in tow.''

The river was quiet Wednesday afternoon, with no official closures and no reports of problems, according to Hall, state sportfishing officials and people at the river.

"We've not seen any bears today," ferry operator Dianne Owen said. "The fishing is slow, and there's actually very few people on the river."

The bear's killing and its aftermath is the latest major conflict between people and bears at the famous salmon stream, where a young man was severely mauled two years ago and anglers have been constantly urged to stop leaving salmon, guts and gear within reach of bruins.

Lots of bears have been reported foraging for fish among people this summer, according to area wildlife biologist Jeff Selinger. Some anglers appeared to handle their gear and fish better than in previous years.

"I think it's better than it has been and people have been making an effort," he said.

Longtime Russian River angler Dean Cornett of Cooper Landing disagreed. State and federal officials need to patrol the river more often, he said, and should consider closing the stream at night.

"People that you have out there (at night) can't see, they are snagging, and a good many of them are drunk and armed," he said. "There needs to be more oversight."

Cornett and his wife, Nina, offered a $5,000 reward for the arrest and conviction of the person who shot the sow, he said Wednesday.

The sow and its three offspring had worked the river for salmon off and on all summer. The sow appeared to be a savvy adult bear that stayed out of conflict with humans, several people said.

"She had posed no threat to anybody," Owen said. "The cubs were getting rambunctious, but that's what they do."

The tolerance of the dead sow was remarkable, Bishop said.

When one angler played "tug-of-war" with one cub over a stringer of salmon, and another man began throwing rocks at a cub, the sow showed no aggression.

"Grandpa had a kid on his hip, and he's throwing rocks at one of the cubs," Bishop said. "If one of those rocks had actually hit the cub, who knows what might have happened."

The most recent incident surfaced Sunday, when people reported seeing a wounded bear sitting in the river at a place called the Cottonwood Hole, Hall said.

Rumors that someone unnecessarily shot the bear were spreading, too -- by word of mouth, e-mail and Web site postings.

"Sunday morning, about four shots were heard up in the campground," said Bishop, the campground host. "And then we heard some guy was bragging he killed a bear.''

A federal officer investigated on Sunday, and found the three cubs rummaging for fish in the stream. One of them favored a foot as though it had been injured. But the officer didn't find the sow or see a dead bear.

Federal and state officials now suspect that the first report was about the wounded sow. One of three cubs was seen limping on Tuesday, after the sow was dead.

"It seems to fit," Selinger said.

Then, on Tuesday, refuge officers investigated another report that a backpack and fishing rod had been left abandoned along the trail just upstream from where the Russian empties into the Kenai, Hall said. The man who made the report said he'd heard noises in the brush that sounded suspicious.

Refuge officer Chris Johnson found the backpack about 25 yards upstream from a sign marking the boundary of a fishing sanctuary on the southwest bank of the river, then began walking about 30 yards farther into the dense grass and brush, Hall said.

One of the 250-pound cubs charged. Then another. And another. All came from the same spot, Hall said.

"After the bears veered off and ran off, and he went in to look to see what they were on," Hall said. "When he did, he found a big sow that had been shot."

Selinger and Johnson later tried to remove the carcass with a litter, but it was too heavy, Hall said. A state forestry helicopter slung the carcass to a pickup truck in the ferry parking lot that afternoon.

By then, the backpack was gone, apparently reclaimed by its owner.

Selinger said he examined the bear and found a wound in its side and one in a rear foot. A necropsy performed later recovered two rifle bullets, Hall said.

"The part that really bothers me is whoever did this should have reported it," Selinger said. "You should do it because it's the right thing to do, and because the law requires it. But if nothing else, you do it (for) public safety, because you have a wounded bear."

Daily News reporter Doug O'Harra can be reached at do'harra@adn.com . Daily News reporter Craig Medred contributed to this story. He can be reached at cmedred@adn.com.