i would worry for many things, there safty, the mental stability and so many things.
i would hope this person can get away safely.
some resporces would be to call the police to areast
or call this 1-877-988-5559. there are also sites.
if your friend is in this problem there are things you can also do to help,
if you see this happening try to record it or call the police.
you and your friend also have a voice to speak out