Many towns of southern Pakistan have been evacuated as rising flood waters threaten hundreds of thousands of people in the region. A major breach in flood defences outside the town of Shahdadhok has left soldiers making strenuous efforts to build emergency barriers.Another breach occurred in the Kot Almo area in Sindh province, forcing thousands of people in the southern Thatta district to flee from their homes. Further downstream, about 400,000 people have been told to evacuate the towns of Sujawal, Mir Pur Batoro and Daro.Fleeing villagers have been heading north, jamming their possessions into vans and cars or leaving with their livestocks on foot.