The steering wheel wouldn't turn?

Just recently after we had really cold weather, to warm it up prior to driving. Once the car had been running for about 10mins, as I went to drive the steering wheel wouldn't turn. I thought this was due to the cold weather and the lines had frozen. However since then the weather has warmed and the steering wheel still isn't turning. Prior to this I didn't see any problems or feel any difference in its driving abilities. Does anyone know what could have caused this or what's wrong with the vehicle? The closest BMW mechanic in this area is over 100 miles and its hard to get there without a working vehicle.