Like bob said get the cops involved and show them what you found...that way there is also a record of it just incase anything happens...people get stupid now days
that has a good and bad side to it if it has a blinking light they may not even mess with it, knowing it may sound an alarm, and if it doesnt have the light, they go to mess with it the alarm sounds and you might catch them in the act..
EFFEN Thieves ..they did that right in front of your house!!that takes balls...glad to hear they didnt get anything..too bad they didnt at least get a couple broken legs ,arms