Most UPVC doors are easily opened without a key. Everyone thinks with their multi point locking systems they are really secure... Wrong... most Euro locks are fairly simple to drill out or open otherwise.
When I drill them out I always use an 8mm drill, dont use a 12mm or you may damage the lever plate (more expense).
Dont drill straight through the keyway or your drill bit will snare and snap.
Have a look at one I drilled earlier.
http://i39.photobucke...in/drilledouteuro.jpg