Nicholas Sheley

Nicholas Sheley during his 2012 murder trial where he was found guilty of killing Ronald Randall, 65, of Galesburg and Russell Reed, 93, of Sterling, Illinois. He was also convicted in May of beating to death Kilynna Blake, 20, her 2-year-old son Dayan, Brock Branson, 29, and Kenneth Ulve, 25, in an apartment in Rock Falls, Illinois. (Michael Tercha, Chicago Tribune / October 29, 2012)

A man serving two life sentences for a pair of Illinois killings was sentenced to four more on Monday, concluding criminal prosecution of a man authorities say committed a series of eight murders in two states.

Rock Island County Judge Jeffrey O'Connor issued Nicholas Sheley, of Sterling, four sentences of life in prison for killing four people, including a 2-year-old boy, in a Rock Falls apartment in June 2008, according to the Illinois Attorney General's office.

In May, Sheley, 35, was convicted by a Whiteside County jury of the Rock Falls murders, the office said. He was found guilty on four counts of first-degree murder.

"Life in prison is the only appropriate sentence under Illinois law for these heinous crimes," Attorney General Lisa Madigan said in a statement. "Today's sentencing ensures that Nicholas Sheley will continue to pay for his actions for the remainder of his life."

Sheley is already serving two life sentences for the slayings of a Galesburg man and another man from his hometown of Sterling. He is also accused of two murders in Missouri following his crimes in Illinois.

"It is fitting that a lifelong criminal has received lifelong sentences of imprisonment for his horrific acts," Whiteside County State's Attorney Trish Joyce said in a statement. "My hope is that the families of the victims find some sense of peace and their suffering lessens with time." | Twitter: @skbaer