Wanna find an action movie produced in the 80's or early 90's

Hi everyone,

I tried to look up a movie on Internet. I thought maybe you could help me if I describe you the final scene as far as I remember. The movie seems to be produced like in late 80's or early 90's.

It's about a terrorist attack planned on US soil and the perpetrators seem to be from Middle East. An African-American guy gives them support in their plans. One scene I remember at the end of the movie was like, a guy wanting to help the perpetrators to escape, lands with a helicopter on the roof of a building. The guy gets off the helicopter and lights up a cigarette and an officer or someone like that appears on the roof and fires with a machine similar to a bazooka, killing the guy who tries to escape with the helicopter.

Could someone give me an idea which movie it's about?

Thanks in advance :-)