Killer militant robots. Please relax
It simply isn't going to be any bigger threat than other ways of killing people today, and I'd be far more worried about a 60 year old technology in loose nukes.
In a sense, the professor is correct. Robots already pose a significant threat to humanity. The most vicious robot requires no recharge, lasts for decades, and has maimed or killed hundreds of thousands of people already: Land mines.
The fact is that there are far more reliable methods of killing people than using robots. Intelligent robots are a ways away, and the real threat here is the militant interested in killing people, and not the specific tool they use.
There is a huge bias in the media and Hollywood against AI, and I think it very much works against real progress in subtle ways. People should be more reasonable about things, and not cry Terminator! whenever a robot is used.