An Illinois man has pleaded guilty to one count of first-degree murder for setting a house fire that killed four children.

Derrick Twardoski accepted a plea deal Wednesday in a Randolph County court. The 34-year-old faces up to 60 years in prison.

He previously pleaded not guilty to four counts of first-degree murder in the May 2013 deaths in Percy. The fire killed siblings ages 12 and 9 and 5-year-old twins.

Prosecutors haven’t disclosed a motive.

The county state’s attorney says the children’s family supported the deal because it avoided a trial.

Twardoski will remain at the county jail until sentencing in October.