Yes, the fire turned out to be legit. It gutted the travel agency on the ground floor. The good news was that the cement walls of these structures limits the ability for the fire to spread. A wood-framed building would have been a different story.
So there wasn't much danger of the building collapsing or anything. The biggest concern for our offices, and the biggest concern about going back in the building, was smoke. In ended up being smokier in the stairwells than I thought and I did feel it in my throat the rest of the day. I'm removing necktie from my list of authorized breathing masks.
There were two theories about the cause of the fire: faulty wiring or insurance scam. This time it seems to be the former.