CHICAGO (STMW) — A west suburban man already charged with kidnapping and sexually assaulting a woman at gunpoint is facing more charges for trying to have a witness in the case killed, according to police.

On June 29, 2015, Donald E. Perkins of Oswego was charged with aggravated criminal sexual assault, aggravated kidnapping and being an armed habitual criminal, according to a statement from Oswego police.

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On July 6, 2015, Kendall County sheriff’s detectives and Oswego police learned that Perkins, then an inmate in the Kendall County Jail in Yorkville, was “soliciting the murder of an acquaintance,” according to a statement from the sheriff’s office.

A joint investigation was started and on Tuesday, Perkins was charged with solicitation of murder for hire and solicitation of murder, both Class X felonies; and conspiracy to commit witness intimidation, according to the sheriff’s office.

The original charges stemmed from an incident on June 28, 2015, when Perkins abducted a woman he knew at gunpoint at a home in the 400 block of Madison Street, according to police.

Officers were called about 4:30 p.m. to the home and were told that Perkins had forced the woman into his car at gunpoint. He then forced her “drive around for approximately two hours and at some point, allegedly disposed of the firearm in a lake in Aurora,” police said.

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Perkins then had the woman drive back to the home on Madison Street, where police were still investigating. He was taken into custody without incident, and the “gun believed to be involved was later recovered from a lake in Aurora” by the Aurora Fire Department Dive Team, police said.

Kendall County sheriff Dwight Baird praised the “joint efforts of detectives” from his office and Oswego police, saying in the statement, “Cooperation between law enforcement agencies is vital to ensuring the safety of the citizens…”

Police would not identity the alleged target of the murder for hire. “We are not releasing victim information to maintain the integrity of the investigation as well as to protect victims,” an Oswego police spokesman said.

Perkins’s bond is now set at $1.5 million for the new charges. His next court date is scheduled for March 24.

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(Source: Sun-Times Media Wire © Chicago Sun-Times 2016. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)