Who is responsible for the collapse of plasco mall?

A massive fire erupted on Thursday in a mega mall in downtown Tehran, bringing the whole the 17-story building down. People now ask who is responsible for the disaster. Some accuse Tehran's mayor Bagher Ghalibaf for the incident responsible, others talk about the responsibility of the owner of the building, the "Organization for Poor" which is under the control of Supreme Leader Ayatollah Ali Khamenei.