Help! '87 Range Rover Won't Start

I left my 87 Range Rover in a parking lot today after it wouldn't start. Everything was fine when i went into the store, but when i came out 10 minutes later the key wouldn't turn in the ignition. I tried jostling the wheel, taking it in and out of park, rolling the car in neutral back a few feet and turning the wheel -- nothing. The key will go in, but won't turn at all.

Any Ideas?

is your power steering locked up?

No, the wheel can turn.

Without the key in the ignition I was able to put the gear shift in neutral and push the car back and forth while twisting the wheel.

Why?

i don't know then, sorry. is it the ignition switch is locked up? can you get any power at all. (i.e. headlights)