A suspected child killer in Illinois may be connected to another woman's murder in a hotel room about 60 miles away, police said.
Antonio Monroe, 44, was arrested after allegedly kidnapping and killing Destiny Rene Huggins, ten, and strangling her six-year-old sister in a random attack Saturday afternoon.
The two young girls were playing in a suburban neighborhood of Rockford, Illinois just outside their home at the time.
There's evidence to suggest that Monroe may be involved in the July 5 dead of Natalie Negray, a 24-year-old woman found dead in a hotel room in Schaumburg, Illinois, three days earlier, according Schaumburg police.
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Monroe was with Negray the night she died, Schaumburg police said, according to Fox 32 Chicago, but her manner of death is still under review.
Circumstances around Negray's death, including how she was killed, and details of the investigation remain scarce a week after her death.
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Fox News Digital left a message for the investigative unit in Schaumburg's police department.
Negray died less than a week before her 25th birthday, according to her obituary, which says, "Taye, as she was fondly called, lived a vibrant life filled with passion and joy.
"She found great pleasure in expressing herself through art, makeup, modeling, and music. Her creativity and talent were admired by those who knew her."
As of Thursday morning, Monroe hasn't been charged in connection with Negray's death, but he remains in Winnebago County Jail on $5 million bond for the alleged attack on Huggins and her sister.
The young girl's death shook the community and the city of Rockford, including the city's mayor and police chief, who said that "sick individuals" had changed the city.
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Huggins' family and friends rallied around the grieving family to pray and release balloons in Destiny's honor and set up a GoFundMe.
"(Destiny) loved her sisters … She didn't deserve this," a family member posted on Facebook. "Sleeping is just impossible she was only a baby.
"God wanted another angel, but we wasn't ready yet," she wrote.
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Rockford Police Chief Carla Redd said during a press conference, "We’re not living in a time where you just leave your kids outside playing and no one to watch over them.
"Kids aren’t doing anything wrong, but unfortunately there are individuals out there that will cause harm to them."
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Monroe was charged with first-degree murder, attempted murder, two counts of kidnapping and aggravated battery/strangulation for the alleged attack on the young girls.
"I have a seven-year-old daughter, and I just don’t understand how someone has this in their being to do something like this to something as sweet and beautiful as that," Rockford Mayor Tom McNamara said during a press conference.
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More charges maybe filed, Rockford police said earlier this week.
Monroe is a registered sex offender who was convicted of sexually assaulting a 19-year-old victim when he was 31 in Peoria County, about 140 miles south of Rockford.
Fox News Digital's Emily Robertson contributed to this report.