Alarm setting itself off HELP!!!!

At various times, especially in the early morning(between 5am-6am), my 99 Toyota 4runner limited alarm will go off for no apparent reason. This morning it went off @ 6am on the dot, yesterday it was @ 5am on the dot, is this simply coincidence or is the truck possessed? I checked to make sure that their are no loose connections under the hood but have had no luck. I do not have a wireless remote so I have to run outside & unlock the doors to shut it off. Please help before my neighbors shoot me! Any advice or tips will be greatly appreciated by not only myself but my neighborhood too. Thanks! :banghead: