an investigation of the event concluded that the event was not caused by a terrorist attack. this was based on the testimony provided by many of the wedding guests present in the building during the disaster. witnesses reported seeing a dangerous sag in the floor moments before the collapse. an initial inquiry blamed the collapse on the pal-kal method of constructing light-weight coffered concrete floor systems which was banned shortly after the completion of the wedding hall since it was known and proven to be unsafe. further review pointed to a combination of two alternative causes.