Four men have been charged and numerous guns and deer antlers seized after the conclusion of a five-year probe into illegal poaching.

Tip-offs from the public led The Minnesota Department of Natural Resources to a house owned by 37-year-old Joshua Liebl in Dawson, Minnesota, on October 21.

It is there that conservation officers seized 37 guns, 28 sets of deer antlers, four sets of elk antlers and a set of mule deer antlers, it is alleged. They also discovered a fully intact, untagged piebald deer in a freezer.

Liebl – who lost his hunting privileges in 2013 because of a conviction in South Dakota – only registered four deer since 2004, the Star Tribune reports.

A separate search of his car that same day resulted in the seizure of a freshly killed buck, as well as more guns and ammunition.

The investigation was called "Operation TIP Works" after it was initiated following calls made by members of the public to the Turn In Poachers (TIP) program, which was formed in 1981 to curb illegal game and fish harvesting in the state.

"Cases such as these go to show the importance of TIP in protecting and preserving our natural resources," said DNR spokesman Lt. Gary Nordseth.

The charges

The people charged at Lac qui Parle County District Court are as follows:

• Joshua Liebl, 37, of Dawson, Minnesota. Charged with gross misdemeanor transporting illegally taken big game, gross misdemeanor use of an artificial light to take deer, hunting during prohibited time, gross misdemeanor trespassing, and two counts of failure to register deer.
• Kevin Martinson, 58, of Plymouth. Charged with illegally lend/borrow a deer license.
• Nate Viesman, 32, of Watson. Charged withi llegal party hunting, lend/borrow a deer license, over limit of deer and two counts of failure to register deer.
• Daniel Lien, 33, also of Dawson. Charged with gross misdemeanor aiding and abetting unlawful transportation of big game.