Pakistan floods threaten key barrage in southern Sindh

Waters have exceeded the danger level at a key flood barrier in Pakistan's southern province of Sindh.

The Sukkur Barrage overflow means Sindh faces as much devastation as that seen further north in Khyber Pakhtunkhwa and Punjab provinces, say experts.

Enraged survivors have been physically attacking government officials in flood-hit areas, amid widespread anger at the pace of the relief effort.

At least 1,600 people have died in the region's worst deluge in 80 years. With more than 14 million people already affected, the monsoon rains show little sign of abating.

Flood waters have roared down from the north to the agricultural heartland of Punjab and on to southern Sindh along a trail more than 1,000km (600 miles) long. In the early hours of Monday morning, the water flow coming down Sindh's Sukkur Barrage was recorded at up to 1.4m cusecs (cubic feet per second). It can only withstand 900,000 cusecs.

Upper Sindh is already under water, and rescuers are continuing to evacuate thousands of families from the province, where the banks of the swollen Indus river are at risk of bursting.

Prime Minister Yousuf Raza Gilani said on Sunday the country had gone back years as he visited Sindh, where hundreds of thousands of people have already been displaced.

With roads, bridges and railway tracks washed away, and deadly landslides increasing the isolation of many of the worst-hit areas, aid workers are having to use donkeys to deliver relief.

The entire Swat valley was cut off at the weekend, with even helicopters unable to reach it because of the poor weather.

"It's hard to get supplies there. I would like to emphasise we are moving by foot or donkey. We are unable to get in to most places of Swat Valley," Maurizio Giuliano, spokesman for the UN Office for the Co-ordination of Humanitarian Affairs, told news agency Reuters.

In the far north of the country, dozens of people were killed when two villages were buried in mud and rocks. Nearly 30 bodies were recovered from rubble after Saturday's landslides in Gilgit-Baltistan province.

The UN has said that Pakistan will need billions of dollars in aid to recover.