What movie is this? Please help.

I remember I saw this movie when I was younger (around 10 years ago). I was looking for it on IMDB but unfortunately can't find it. Maybe you can help me out.

Things I remember it contained:

- Plot#1: It covered a spaceship that was monitoring earth and covered a huge cell in which a very dangerous alien was locked
- Plot#2: Somehow the alien manages to escape to earth and starts killing people. Than someone from the spaceship also goes to earth and tries to find and kill the alien.
- the alien could posess people (as far as I can remember) and those people had totally black eyes and were talking in a strange language
- there was a scene in which a guy was writing strange signs on a board
- the people on the spaceship I mentioned were also humans and watching satellite television in space
- the movie had some nice car chase scenes and was pretty scary

Thanks in advance if you can help me.


(Grissom): -Are you a terrorist?
(suspect): -Depends, are you terrified?