Thor's Hammer: Stolen?

Last week Odin issued an official notice that Thor's beloved hammer, Mjolnir, has been stolen. Reportedly, there was one casualty during the robbery, and the other 2 assailents are at large, and unknown. The Norse are offering a collective $50 Million bounty for whomever returns Mjolnir, and an addition $25 Million if they bring the thieves alive, $10 Million if dead. Thor hasn't provided a description of the perpetrators, but said "I could recognize them on sight."

This is a serious issue, as Thor has been notorious for going on rampages when his hammer has been stolen in the past.