95 Toyota pick up timing belt

I am having problems with my nephews truck. It is a 95 toyota pick up wit the 3.0 cyl motor. He was driving down the rd the other day, and the truck started overheating. He pulled off to the side of the rd, and waited for it to cool down. When he tried to start it, it would just turn the engine over real fast but wouldnt start. I went to look at, and found the timing belt melted and broke, along with the water pump pulley, tensioner pulley, and the pulley between the camshafts locked up. First question, what would have caused this? Second, do you think the engine itself is hurt? and last question, how do I get it back into time, I have never did one that the belt is broken. It also has the spring type tensioner. Also how do I get the pulley off that is between the 2 cams?

Thanks in advance

I'm not real familiar w/the 3.0, but if one of the pulleys froze-up, it could cause the belt to go out. Or the belt itself may have been worn out.

If you're contemplating doing the work yourself, I'd get a FSM and check out the procedure, to see if it's someting you can handle. Also Search the net for how-to articles, there's probably a bunch. I've done a few 22R TC's, and it was fairly simple.