(CBS) – A convicted sex offender was taken into police custody Friday afternoon after he allegedly knocked a 4-year-old boy off his bicycle and tried to abduct him before being stopped by Good Samaritans.

The incident happened around 12:45 p.m. near Olson Park in Woodstock, a far northwest suburb.

Kevin A. Sorenson (Woodstock Police)

An adult suspect pulled the boy off his bicycle and began to run off with him, Woodstock police said in a news release. When the boy and his friends began screaming, two Good Samaritans freed the boy and restrained the suspect, police said.

“Because of the quick, heroic actions of the Good Samaritans and responding officers and detectives, the child was not physically injured,” police said.

Kevin A. Sorenson, the Woodstock man taken into police custody, had a previous conviction for a child sex offense, though he was no longer required to register, police said.

Sorenson, 39, was charged with aggravated kidnapping, aggravated battery, unlawful restraint and aggravated criminal sexual abuse, according to police.

Sorenson will be held at McHenry County Jail, pending a bond court hearing.