2002 Dodge Caravan Ignition Locked/Frozen

Other Category problem
2002 Dodge Caravan Engine Size unknown Front Wheel Drive Automatic 107k miles

The ignition of my Dodge caravan 2002 is locked. When I tried to start it yesterday the key would not turn although the wheels would turn. I trying to turn the wheels in hopes of allowing the key to turn. At that point the steering wheel went into the locked position and will not move. I should note that this is my first winter with this van. The temps outside this week have been about 25 degrees F. My mechanic came and looked at it but he is stumped too. Please help.I have small kids and no transportion!