Ford Focus

I have a 2000 Ford Focus LX with aproximately 135,000 miles. The car started making a strange noise and I pulled over and popped the hood and it suddenly stalled. Then I drove it home about 1 mile, and popped the hood again (it was still making the noise) and I saw that the balt was not turning at all and there was a peice that looked like it was off center and that seems to be the reason that the belt is not turning what could that be?
January 25, 2007.

Which one?
A, B or C?

A is the crank, b is the idle C is where the alternater is.

Is this your engine?