Six people died while 16 others were injured when a passenger coach overturned near Sassi Toll Plaza on the National Highway here on Tuesday morning. Two women are among the dead. According to rescue officials, the injured people have been shifted to hospital. The passenger coach was on its way to Thatta from Karachi. According to rescue sources the bus hit the pillar of the Toll Plaza after its brake failed and then overturned. Traffic accidents have become a frequent occurrence in Karachi as major roads of the city are dug up for construction. This has disrupted the daily life of citizens in many ways.