Could be many different ways of getting in
Slim Jim is probably the most common way. It's basically a slim piece of metal with a hook on it. Commonly used by tow truck drivers to tow cars. Petty thieves can often make them outta of coat hangers etc.
Other option is to bend the windows and use a hanger to unlock the door.
If someone has some sort of master key set they might luck out also.
Better thieves tend to just go straight for the door lock which often turns off certain factory alarms.
Here's a FAQ I wrote years ago
http://www.revscene.net/forums/forum...ead630424.html