I read that when the fire erupted people were not allowed to exit unless they have paid which caused many deaths and time wasting..
The stage was on one side, and the exit was on the other. It takes a couple minutes until the security guards (in such a crowded place) can see the smoke. They saw a lot of people running around, screaming and shaking but they could not see what exactly was going on. They thought it was a mass fight or a petty fire which was under control. When they saw the big smoke pouring in they opened the doors, although by then all those 200 people lost their chance. The building did not have any sort of fire sirens or sprinklers.