Grinding noise when turning the key

I have a 2005 subura impreza rs 2.5 and there been
a rattling/ squealing sound. We assumed it was
the a.c. compressor so we cut the belt and it stop
but there was still a rattle and so we thought the
alternator was going bad well while I was driving
the rattling got louder and my car shut down. We
hooked jumper cables to the battery to try to move
it well when I turned the key there was grinding
could this be bad timing chain and alternator?