Twitter Account Hacked?

[L]

Someone is on my Twitter account via iPhone and they won't log out. They are changing my settings and writing Tweets which are offending to others. Is there any way I can make them log out without going on their actual mobile?

[Ben]

ssh into their ip and remove the application

[Reece]

A hacker would hide their IP address so ignore first answer, tell twitter they have a great service for this sort of problem.