I saw this on TV in, I believe, the early 80s. It's about a group of people that are being held hostage by kidnappers and among them is an Air Force officer that is acting as a secret courier for a deadly biological agent. I can't remember most of the details, but the ending is that the lead kidnapper forces the Air Force officer to help him escape in a small plane. In the process, the hijacker finds the cigar case, and believing it to be a cigar, opens it to find the deadly agent. Rather than having this agent escape, the officer crashes the plane, sacrificing himself and his abductor. I've search all over IMDb for this to no avail.
Edit: A few additional details: there was a girl and her mother being held hostage and the girl ended up sleeping with one of the hijackers to save the rest of the hostages (this part is fuzzy and I think most of it was inferred). Also, I believe this movie may have come out in the 70s (but not 100% certain).