Tens of thousands of people in southern Pakistan are fleeing a threatened flood-surge, three weeks after heavy monsoon rains first hit the country.

In one village in Sindh province, Shahdadkot, people are trying to salvage their belongings amid fears a protective barrier will be breached.

An estimated 4m people have now been displaced in the city of Sukkar alone.

Meanwhile, the World Health Organization (WHO) says diseases are spreading in affected areas.

Sindh in the south is now being described as the country's worst-hit province, with officials saying at least 200,000 residents have fled in the last 24 hours.