LITTLE FALLS -- Little Falls police say an open investigation into a man's body found in the Mississippi River Sunday has led to another mystery.  Police say 36-year-old Michael Arndt has now been reported missing.

Arndt and 34-year-old William Blake were supposed to meet near the Burlington Northern Railroad bridge last Wednesday. That's the last anyone saw of Blake before his body was pulled from the river Sunday. Arndt is now missing and police are looking for any information which may lead to Arndt's whereabouts.

If you have any information on the case, you're asked to contact the Little Falls Police Department at (320) 616-5570.