I don't think that the collapse could have been caused by the fire. That leaves the only other two possibilities being that it collapsed because of a few floors "buckeling down" like bongman said or that it was caused by thermite or some other shit.

I did some research and basically I found out that there's absolutely no way that the center columbs where melted by jet-fuel. Steel melts at 2500 degrees F. The Jet fuel burns at around 425 degrees F and it would have all burned up within a minute or two leaving shit around the office to burn until the buildings actually collapsed. And you have to take into account the fact that these planes couldn't have been fully fueled. And steels critical tempurature is at 1,100 degrees F, where it loses about half of it's stability.

Remember that the North tower had an intense fire in 1975 and suffered no structural damage.

In any case, a fire couldn't possibly have brought down those buildings. It's scientifically impossible. I'm sure there's a logical explanation that the official report fucked up on. -the official report says that they collapsed solely because of a fire-