What Evidence Is There That Saul/Paul Actually Killed Christians?

My take on this would be that the answer is "no" in the physical realm because Saul was a Pharisee and therefore obeyed the law to the letter. Was he an accomplice? Surely he was, as he held the coats of the ones who killed Steven and had people thrown in prison. That would make the answer in the spiritual realm "yes", as the Word speaks of if you hate a brother or sister you are a murderer, so standing by and letting someone stone another person to death would spiritually make you guilty of the same.