Chattanooga Police are on a mission to retrace Deborah Underhill's last steps.
Nathan Hartwig with the Chattanooga Police Department, says, "We just want to start our investigation now, and start tracking where she was."
They believe last Thursday she was staying at a home on Tennessee Avenue.
Around 9:30 in the morning, she checked into a community center for people with mental illnesses.
It's called the AIM Center.
Hartwig adds, "But since her check in at 9:30, we're not sure exactly what happened, when she walked out. If she walked out right away, we're still trying to figure all that out."
Chattanooga Police tell us Underhill was reported missing late Thursday evening.
The next day fishermen found her body in the Tennessee River, just past Moccasin Bend.
Hartwig says, "There weren't any visible signs of foul play, but that's why we have to wait for the medical examiner's office."
They did wait, and while the Hamilton County Medical Examiner's Office would not release their findings to us, they told police some injuries on her body were suspicious.
Hartwig adds, "It's still just an undetermined death. It hasn't been ruled a homicide yet."
Now, investigators are asking you, Do you know who this mother of two was with last Thursday or Friday?
Deborah Underhill also went by the name of Deborah Swafford.
If you have any information on this case, call Chattanooga Police.
We also reached out to the AIM Center today, but they did not return our call.