It was a combination of things. Victor said he was spotted at the crime scene so he didn't exactly help his cause much. Plus I think Gus was wanting to scare the living **** out of walt and jesse after what had happened. He had to remind them who they were working for.
So....what about the blood on Mike's finger? (nothing else happens in that scene)
Did he kill Gus??
He said "Youll never see him again"
