Updated 03/03/11 – 12:09 p.m.

LANSING, Ill. (CBS) — Two have been charged with sexually assaulting an 11-year-old girl during a sleepover party in south suburban Lansing.

Steven Johnson, 19, and Daniel Rucker, 20, were both charged with predatory criminal sexual assault, a class X felony, according to a release from Lansing police.

At the Markham courthouse Thursday morning, Johnson was ordered held on $750,000 bond and Rucker on $500,000 bond, according to Cook County State’s Attorney’s office spokesman Andy Conklin.

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Police say Johnson and Rucker were at a sleepover party this past weekend for the 12th birthday of one of the girl’s classmates. The party was held at Johnson’s family’s home, in the 17800 block of Chicago Avenue in Lansing, police said.

Other children and adult family members were also present, police said.

The party started Saturday and went on late into the evening, as the young girls played games and danced. When bedtime arrived for the children, the 11-year-old girl was sent down to the basement to get blankets, police said.

It was at that point that Johnson and Rucker attacked and raped the girl, police said.

“As a parent you would never think something like this would take place at a 12-year-old’s birthday party,” Lansing police Detective Sgt. Scott Bailey said in the release. “What happened to this young girl is horrific.”

Steven Johnson, Daniel Rucker

Steven Johnson (left) and Daniel Rucker are charged with sexually assaulting an 11-year-old girl at a birthday party. (Credit: Lansing Police)

Johnson was arrested Monday night, after Lansing police executed a search warrant and combed the basement for evidence. Rucker, of Calumet City, was arrested the following evening, police said.

Counseling agencies are currently working with the victim and her family, the release said. Police are also working with the Illinois Department of Children and Family Services regarding the case and are seeking cooperation from Johnson’s family..

The Sun-Times Media Wire contributed to this report.

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