No casualties have been reported.
The youth belonging to Hebei Province reportedly set fire to stacks of clothes in a warehouse on the 7th and 8th floor of Bairong Shimao Department Store, state-run Xinhua news agency reported.
The police have not released any details of the possible motive.
Over 230 fire fighters were pressed in to douse the fire which continued to rage till late in the evening today.
Fire fighters at the scene said that toxic gas was hindering the efforts to quell the flame.