Sentencing arguments wrapped up today in the case of a man who threatened to kill hundreds of people at last year's Calgary Stampede.

Patrick Deegan

Patrick Deegan, 29, pleaded guilty in January to uttering death threats, possession of unauthorized firearms and two counts of breaching conditions.

Pat Deegan, 29, pleaded guilty in January to uttering death threats, possession of unauthorized firearms and two counts of breaching conditions in relation to an email he sent to the Calgary Fire Department on May 26, 2013.

"There is going to be a machine gun attack at the Calgary Stampede this year," the email read. "Two MG-52s rated at 1800 rpm. There will be over 1,000+ casualties. These machine guns can fire 1,000 rounds before malfunction."

The email prompted a police investigation that led officers to search the homes and cars of Deegan's parents and girlfriend in June 2013.

A Calgary courtroom was told today that police found two improperly stored semi-automatic rifles and one hunting rifle at his parent's house.

'I'm sorry'

One of the weapons had been purchased under the name of Deegan's employer, the Shooting Edge.

At the time, Deegan was on a 12-month peace bond for a violent domestic incident.

One of the conditions of the bond was that he wasn't allowed to purchase or possess firearms.

"I'm sorry," Deegan told a Calgary courtroom today.

The prosecution is asking Deegan be sentenced to three to five years in prison, saying the threatening email was an act of terror and intended to cause fear.

The defence is asking for probation.

"In this modern day world with heightened awareness about crimes of this sort we ought not to become so hyperbolic, reactionary and full of hysterical fear that we lose sight that some threats are real and some are simply not. This was not," said defence lawyer Greg Dunn.

A date for sentencing will be set on Monday.