MADISON - A Monroe man may lose his freedom and some real estate in connection with allegedly sending threatening e-mails to a DeForest police office earlier this year.

James R. Karls, 47, pleaded guilty Friday in federal court to possessing a firearm while under a restraining order. In a separate case, the federal government seeks forfeiture of a building Karls owns at 9th Street and 12th Avenue where marijuana and a psilocybin growing operation were allegedly found.

Karls was a resident of DeForest in 2007 when a restraining order was issued against him in Dane County prohibiting him from stalking or harassing "an intimate partner." In February, Karls allegedly sent four e-mails to the DeForest police officer who had arrested him in 2007 in connection with a domestic disturbance. In one e-mail Karls allegedly threaten to "(expletive)" kill the officer. In another e-mail Karls stated "maybe I'll take my 357 and blow your (expletive) head off."

Authorities obtained a search warrant for the three-unit apartment building Karls owns at 9th Street and 12th Avenue and recovered a .357 caliber revolver, about 200 rounds of ammunition, and a package from an ammunition seller in Texas addressed to Karls, said Assistant U.S. Attorney Rita Rumbelow.

Neither Karls nor his attorney Brian Brophy disputed Rumbelow's statements.

Also recovered were about 5 ounces of marijuana bagged up in various quantities, 6 grams of psilocybin, baggies containing growing psilocybin, psilocybin growing medium, a drug ledger and a smoking device made of glass, according to an affidavit Monroe Police Officer Joshua Heer had filed with the court.

One of the rooms at 824 12th Ave. appeared to be used as a psilocybin growing room, according to Heer's affidavit. The windows were covered with an opaque material and the room had temperature and humidity controls.

Psilocybin has hallucinogenic qualities when consumed and, under federal law, is illegal to grow.

Karls' building is valued at $88,000 and can be seized by the government if it can prove it was used to facilitate the commission of an offense. No court dates have been set in the proceeding.

Rumbelow said Dane County is investigating Karls in connection with the alleged e-mailed threats.

Karls faces maximum statutory penalties of 10 years in prison, a $250,000 fine and three years supervised release on the firearms charge at his July 26 sentencing before District Judge Barbara Crabb.