Vertical rotation of arms with hands

Hello everyone! I have a terrorist model and a weapon model. Terrorist humanoid.Weapons tied to his right hand. He made a character turn behind the camera (so that you can adjust the direction with the mouse).And then I had a question. How do I vertically rotate a weapon with his hands? That is, when the camera rotates up (down), it is necessary that the weapon along with the hands also moves up (down). How to do it? Can arms and arms be rotated vertically through a script? Hands are one with my character, in a hierarchy of hands inside a terrorist

Please! Help me!

Why is no one answering? Is there no solution?

Hey!