On July 25, Maggie Jablonska was out boating with her fiancee, when a speeding boat flew over them. The boat, driven by Richard Stevenson, hit Jablonska, killing her instantly.
He's now charged with numerous crimes, and was just indicted on first-degree murder charges.
On Monday, Illinois Conservation Police released video of a boat on nearby Petite Lake that same day. Police say those on board are not accused of any wrongdoing.
However, investigators want to talk to them because they may have witnessed activity, or possess information relevant to the case.
Anyone who recognizes the boat or its occupants, or who has additional information, is asked to submit information through the Illinois Conservation Police online tip portal: dnr2.illinois.gov/OLETIPHotline/.