Updated

A former Wisconsin grocery clerk pleaded guilty Thursday to making bogus Internet postings warning of terrorist attacks against seven NFL stadiums in 2006.

Jake J. Brahm admitted he posted false information that so-called dirty bombs would be detonated at stadiums having games on Oct. 22, 2006.

Brahm had said the stadiums were in Miami, Atlanta, Seattle, Houston, Oakland, Cleveland and New York City. He admitted the reference to New York was intended to indicate Giants Stadium, in East Rutherford, N.J., where the Jets played the Detroit Lions that day.

Brahm, 22, of Wauwatosa, Wis., pleaded guilty to a one-count indictment that had been handed up exactly a year earlier. The charge, part of the Patriot Act, accused him of willfully conveying false information that the stadiums would be attacked by terrorists with weapons of mass destruction and "radiological dispersal devices."

Brahm remains free on bail and faces up to five years in prison and a $250,000 fine when sentenced June 5 by U.S. District Judge Jose L. Linares.

Brahm admitted composing and posting the threat about 40 times on a Web site between September and Oct. 18, 2006. The message said bombs would be delivered by trucks and "the death toll will approach 100,000 from the initial blasts and countless other fatalities will later occur as result from radioactive fallout."

The posting added the stadium explosions would be praised by Osama bin Laden as "America's Hiroshima" and spark global conflicts.

Brahm's lawyer, Walter A. Lesnevich, said although the law is vague and may one day be repealed, they agreed to the plea because it gives Brahm a chance for probation or a prison term of up to six months.

"He did not put it on a normal news Web site," said Lesnevich, who claimed its original audience didn't take it seriously.

Lesnevich said Brahm "did not think through the consequences" of what might happen when it spread around the Internet.

Authorities found Brahm stocking milk in a grocery. He is now working in his father's wood shop, the lawyer said.

Authorities said Brahm's actions wasted homeland security efforts.

"This was the Internet version of yelling fire in a crowded theater, but to a much wider audience," U.S. Attorney Christopher J. Christie said in a statement. "I don't think anyone needs to be reminded in this day and age how serious and dangerous such conduct is."