ANTIOCH, Ill. (STMW) — A onetime north suburban Antioch firefighter was sentenced to 13 years in prison Friday after he pleaded guilty to the sexual assault of a minor, the Lake County News-Sun is reporting.

Matthew Bielecki, 44, of Antioch pleaded guilty to one count of criminal sexual assault involving a victim between the ages of 13 and 18 years old, a Class 1 felony.

Assistant State’s Attorney Jason Grindel said that if the case went to trial, testimony would show that Bielecki had intercourse with a 15-year-old girl, with whom he held a position of trust as her modeling manager.

The incident occurred between March 4, 2012, and Aug. 4, 2012, Grindel said.

Bielecki had faced more than 20 Class 1 felony charges, including aggravated criminal sexual assault.

His defense attorney, David Weinstein, said Bielecki could have been sentenced to 60 years in prison if convicted at trial.

Grindel said Bielecki must serve at least 85 percent of his sentence, with potential time off for good behavior of up to 15 percent.

He will be given credit for the 610 days he has spent in Lake County Jail toward his 13-year sentence.

He has been held in Lake County Jail in lieu of $250,000 bond since his arrest.

Bielecki must also register as a sex offender for life under the agreement, which was approved by Judge James Booras, and he will serve a period of supervised release after his term is completed.

Bielecki was once a firefighter with the Antioch Fire Department.

He was terminated in 2000 for theft of property, including equipment and uniforms, according to fire officials.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2014. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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