Hello guys! Some time ago I was waiting for my bus in the bus stop, and there was a TV store in front of it. That day the TVs were showing a movie/TV show whose I watched only one scene, but I didn’t listen to any audio.

There was this guy (I believe he was a criminal) handcuffed to a female police officer inside a PD. Then he talks to her (I believe he was asking to make a call) and she allows him to grab the phone, but as soon as this happens he beats her head with the phone and she faints. Then (I don’t remember how) he finds a circular saw and cuts her hand off while she’s unconscious to get rid of her. And then my bus arrived….

Can someone help me finding out what movie was that? Thank you all!