A Riverton man pleaded guilty in federal court Wednesday to growing hundreds of marijuana plants.

Luke Jackson Tilghman entered the change of plea during a hearing before U.S. District Court Judge Scott Skavdahl.

In exchange for the plea,Tilghman probably will serve the low end of a mandatory minimum sentence of five years to six years, eight months because of his otherwise minimal criminal record, Skavdahl said.

However, the court does not necessarily have to accept the agreement of the plea deal when he is sentenced on Sept. 6, the judge said.

During the hearing, Tilghman also withdrew a motion he filed on May 23 to suppress evidence he claims a law enforcement officer found by an illegal search.

When the judge asked how far he went in school, he said he was halfway through a Master's in Business Administration degree and quit.

In January, he was indicted on one count of possession with intent to distribute 100 or more plants. He pleaded not guilty during his arraignment May 6.

Tilghman, who was 33 at the time of his arraignment, remains in custody.

The case started in December when his name surfaced during the investigation of a Casper resident, Neil Arcuri, who had a marijuana growing operation in Paradise Valley.

During that investigation, authorities learned of a growing operation in Fremont County. They forwarded that information to other authorities who executed search warrants at two places and seized 638 plants.

The U.S. Drug Enforcement Agency regards marijuana as a Schedule I controlled substance, meaning it is a drug “with no currently accepted medical use and a high potential for abuse.”