Rear windshield shattered

My '96 Camry was parked outside my home - I went out this afternoon at about 3.30 and found the rear windshield completely shattered - the glass is broken along bothe the edges on the sides - some glass is outside but most of it has fallen inside. There is no other sign of damage - except for the two big holes along the sides. The rest of it is brittle - a slight touch brings more pieces down. Could this happen due to heat? It has been somewhat warm - probably about 80 degrees in the middle of the day - but the car is usually parked in the same spot, and we have had hotter days than this!

wait i just reread it. you said there are two holes near the edges? thats odd. maybe defroster malfunction?

wait i just reread it. you said there are two holes near the edges? thats odd. maybe defroster malfunction?

I haven't used the defroster at all for quite a while - maybe even a couple of months. How do I check for that kind of thing?

What makes you think it wasn't vandalized?

What makes you think it wasn't vandalized?

That was my first thought - but -
1. The way it was broken - two breaks along the two sides - why would somebody choose to break it along both the edges?
2. The way the glass lay about - many small pieces on the ground on both sides, almost as if it had exploded out, and the bigger chunks had fallen in
3. The fact that this is a very safe neighborhood - the parking spot is just outside my home - we have never heard of things like this happening around here

yeah i first thought vandalism but the way its described i dont think so. could you take a pic?

Temperature shouldn't be an issue. My 96 is parked outside all the time in temperatures between 90 and 100+. When I forget to roll down my windows it gets really hot but I've never heard of it exploding a window out. Cars aren't air tight so the pressure should be able to equilize.

Temperature shouldn't be an issue. My 96 is parked outside all the time in temperatures between 90 and 100+. When I forget to roll down my windows it gets really hot but I've never heard of it exploding a window out. Cars aren't air tight so the pressure should be able to equilize.

Here's a picture - what could have caused this?
http://files.automotiveforums.com/gallery/data/500/350907car.jpg

Two hits with a baseball bat?

Or 2 firecrackers taped to the window. It was over the 4th of July weekend.

Mike