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A Philadelphia man has pleaded guilty after he allegedly reported a hoax mass shooting and a bomb threat in response to a disagreement in his fantasy football league, according to police.

Matthew Gabriel, 25, now faces up to five years in prison after he pleaded guilty to two counts of interstate and foreign communication of a threat to injury, according to the U.S. Attorney's Office in Philadelphia. Gabriel's lawyer, Lonny Fish, told NBC News that it's fairly likely that Gabriel will receive 15 months of home confinement when he gets sentenced in January.

Gabriel allegedly had "an online disagreement with a member of his fantasy football chat group," when the victim, who was a student at the University of Iowa, went to Norway to study abroad. Gabriel then contacted the Norwegian Police Security Service, and claimed that the exchange student was going to carry out a mass shooting.

"On August 15th, a man named (the victim) is headed around oslo and has a shooting planned with multiple people on his side involved. they plan to take as many as they can at a concert and then head to a department store," Gabriel wrote, according to prosecutors in the case.

"I don't know any more people then that, I just can't have random people dying on my conscience. He plans to arrive there unarmed spend a couple days normal and then execute the attack. Please be ready. He is around a 5-foot-7 redhead coming from America, on the 10th or 11th, I believe. He should have weapons with him. Please be careful."

According to Fish, Norwegian authorities spent over 900 hours investigating the tip from Gabriel.

On March 22, Gabriel emailed the University of Iowa stating that the same person was intending to set off a bomb on the school's campus.

'Hello University of Iowa, a man named (victim) told me he was gonna blow up the school,'" the U.S. Attorney's Office said.

"While already being prosecuted for one hoax threat spurred by, of all things, his fantasy football league, Matthew Gabriel inexplicably decided to send another," U.S. Attorney Jacqueline Romero told NBC News. "His actions were extremely disruptive and consumed significant law enforcement resources on two continents, diverting them from actual incidents and investigations."