MINNEAPOLIS — The Minnesota Department of Natural Resources said Thursday it was investigating a report of potentially illegal hunting activity on land owned by the dentist who was sharply criticized for shooting a well-known lion in Zimbabwe.

Leah Thompson, who hunts on land in northwestern Minnesota next to property owned by Bloomington dentist Walter Palmer, said that she reported the activity after seeing pickup trucks chasing deer on Palmer’s land last weekend. She said the trucks also were herding deer back onto Palmer’s property.

Chasing or herding deer with a motor vehicle is illegal in Minnesota, punishable by a $200 fine.

Palmer, who became a target of protests this summer for shooting a lion named Cecil while bowhunting in Zimbabwe, issued a statement saying he and his guests weren’t on his property near Barnesville after 11 a.m. Saturday. He said he didn’t own or operate any of the vehicles Thompson described to the DNR.

He called the allegations an “attack on an innocent man,” and said Thompson, whose family owns neighboring property, has “a history of personal animosity” toward him.

Thompson dismissed Palmer’s statement, but acknowledged she and others who hunt on nearby land have complained for years about what they consider unsportsmanlike hunting practices on his property. She also acknowledged she didn’t see Palmer driving the trucks or hunting.

Maj. Greg Salo, an operations manager for the DNR’s enforcement division, said the investigation was in its early stages. He said DNR officials hadn’t made contact with Palmer yet as far as he knew.