TWO people died and 26 were injured, some seriously, in an explosion at a ping pong ball factory in Guangzhou yesterday. The explosion which was followed by a fire, occurred at about 1 pm and severely damaged the factory at KiangNan Main Road in Haizhu district. Firemen put out the blaze by nightfall. The injured, mostly workers at the factory, were taken to hospital in Guangzhou where they were treated for burns. Firemen and Public Security Bureau officers were late last night investigating the cause of the explosion. Reports from Guangzhou suggested it may have been caused by a gas leak.