No charges will be filed in connection with alleged illegal deer "herding" near land owned by Dr. Walter Palmer in western Minnesota last fall, authorities said Thursday.

The Department of Natural Resources (DNR) investigated reports that someone used pickup trucks during the fall hunting season to herd deer back onto land owned by Palmer, the Bloomington dentist and noted hunter who created an uproar when he killed Cecil the research lion this summer in Zimbabwe.

"We interviewed all the witnesses," DNR spokesman Chris Niskanen said, "but … they were unable to provide us with any specific information that would allow us to identify a suspect" who allegedly herded deer onto Palmer's property, prime hunting land near Barnesville.

Niskanen noted that DNR investigators requested interviews and statements from Palmer and the land manager, but neither complied.

Niskanen also pointed out that the alleged incident occurred on a public roadway and that witnesses were unable to provide many details. "Our investigators had no license plate information," Niskanen said, "and the vehicle description did not match any of the vehicles owned by [Palmer] or his land manager."

"Both the DNR and the county attorney concluded that there wasn't enough evidence or any facts to report any charges or warnings in the case," he added.

Under Minnesota law, a person may not use a motor vehicle to intentionally drive, chase, run over, kill or take a wild animal. A conviction brings $287 in a fine and court fees.

A representative for Palmer declined to comment Thursday on the DNR's decision.

When the accusations first surfaced, the representative said in a statement that neither Palmer nor any of his guests were on the land at the time of the alleged herding. "The source cited by the media has a history of personal animosity toward Dr. Palmer," the statement said. "This is just another example of people trying to attack an innocent man."

In early November, a resident of the area, Leah Thompson, said she reported that two pickup trucks had hindered deer from leaving Palmer's property while she was deer hunting on her family's land. She acknowledged that she could not identify the drivers. Thompson said at the time that she had been seeing this tactic on or near Palmer's land "for the past 10-plus years. This is not because of the lion, no."

Palmer's Minnesota hunting refuge lies between Barnesville and Pelican Rapids, about 45 minutes southeast of Fargo-Moorhead. It's made up of nearly 900 acres of rolling hills, oak woodlands and small lakes.

Property records show Palmer bought the core 520 acres in Clay County in 1999 and then added adjacent parcels over the years. He owns another 230 acres on nearby Pelican Lake, in Otter Tail County.

A global furor erupted in early July after news broke that Palmer, a veteran big-game hunter who lives in Eden Prairie, had killed Cecil in a nighttime hunt in Zimbabwe, taking the lion down with a compound bow and then finishing him off hours later.

The lion was baited and the hunt was conducted on private land where, some authorities have said, there was no permit to kill a lion.

Despite accusations in Africa against Palmer, only the professional hunter he hired has been charged in Zimbabwe. Authorities later said they would not be charging Palmer with a crime. An investigation by federal authorities in the United States continues.

In an interview with the Star Tribune and the Associated Press in September, Palmer reiterated his contention from the start that he relied on his guide to ensure that the hunt was legal. He added that if he had known of the lion's stature as a research subject and as an attraction, he would not have killed the animal.

pwalsh@startribune.com • 612-673-4482 jennifer.brooks@startribune.com • 612-673-4008