I had a report this morning from sunny Stoke that my 4-door (parked in the garden) had been broken into

But the odd thing is that all the doors were still locked, there is no broken glass anywhere to be seen, nothing has been taken, but the driver's side window is missing!

The only thing I can assume that has happend is that the window has dropped inside the door.
Now, I know how the window mechanism works but I'm asking for ideas based on experience.......
I would imagine there is two possibilities:
1) The window has just dropped on it's own.
2) The window has been tried to be forced down from the top, and it's caused the arm end to pop out of the guide at the bottom of the glass thus causing the window to drop down.
I can't see the car myself until the weekend, but I will hopefully get some more info tonight over the 'phone..............
Any opinions/ideas folks??