CHICAGO (WLS) -- After a worldwide social media audience watched 17-year-old Kyle Rittenhouse open fire in the middle of a Kenosha, Wisconsin street with an AR-15 style rifle, he returned to his family's home in Chicago's northwest suburbs.
The I-Team has learned from federal investigators that the gun was legally purchased, however, authorities are still working to figure out how it ended up in the teen's hands.
A few hours later, when Rittenhouse voluntarily surrendered to Antioch police, "our department did take possession of two Smith and Wesson M&P 15 Rifles" the ABC7 I-Team was told Thursday by police chief Geoff Guttschow. "These rifles were subsequently turned over to the Kenosha Police Department in furtherance of their investigation into the shootings that took place there," chief Guttschow said.
Even as the teenager is being held in a Lake County lockup while extradition proceedings play out, investigators on both sides of the state line work to "determine when, where, how and by whom the firearms were purchased; and to determine if any crimes were committed in our jurisdiction in doing so," Guttschow said.
Authorities tell the I-Team decisions are expected soon on whether additional individuals will be charged in connection with the weapons, the murders of two people and wounding of a third in Kenosha on August 25.
Investigators have not revealed whether one or both of the rifles were fired by Rittenhouse, or others, during the destruction in Kenosha that followed the police shooting of Jacob Blake. However, there could be further legal complications for the teenager if he transported the guns across the state line.
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His attorneys in the double murder case maintain that Rittenhouse did not bring the assault-style rifle from Illinois to Wisconsin prior to last month's killings. They say the rifle was owned legally by a Wisconsin friend and handed over to Rittenhouse the afternoon of the killings as he and a friend tried to help police defend Kenosha businesses that came under siege by looters and vandals. They maintain under Wisconsin law it is legal for the friend, not a minor, to have provided the rifle to Rittenhouse.
Rittenhouse is charged with possession of a dangerous weapon, not with transport across state lines or possession of a stolen or illegal weapon.
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Further, Rittenhouse's attorneys contend that he never crossed the Illinois border at all that day because he had slept at a friend's place the previous evening so he could go to work as a Kenosha pool lifeguard.
The teen's attorneys have not responded to I-Team questions about his movements, the guns or how he obtained the weapon seen in his hands on video that went viral. His legal defense crowdfund is now at nearly four hundred thousand dollars.