I remember seeing this movie about ten years ago. It was an American color film. Looked like it was filmed in anywhere between mid 80’s to early 90’s.

The basic premise is that scientists accidentally or intentionally release a poison gas inside an underground research facility. That was located in what looked like the Arizona desert. The poison/virus/plot device turns everyone who gets infected in to emotionless psychopaths. They’re still capable of talking and doing normal tasks and working in a group, but they can’t stand light, so they break most of the brighter lights in the facility. The government wastes no time sealing all the entrances and they send a team of soldiers down in to the facility. But they get ambushed by the scientists first pretending to be normal, until they lead the soldiers in to a bottleneck and the soldiers are killed by the laboratory personnel. As far as I remember the main character’s daughter is stuck inside a room in the facility for some reason and the main character (man) enters the facility with his partner through a ventilation shaft, that the goverment has not sealed yet. This is where my memories about it fade. It could have been a tv movie, since it’s so hard to find, I presume so.