Torrential rains have caused massive flooding in Sindh, a province in southern Pakistan.

The country’s Prime Minister Yousuf Raza Gilani has cancelled a visit to New York next week for the United Nations’ General Assembly in order to supervise relief efforts.

According to reports, about 6-million people have been impacted by the floods, amidst fears that some regions may be waterlogged for months. Humanitarian and aid organizations are calling for emergency relief, warnings of an impending disaster. About 270 people are believed to have already died from the flooding.

The Pakistani government was criticized for a slow response to devastating floods from last year, which affected 20-million people and killed almost 2,000. Many damaged infrastructure have still not been repaired, nor has the government prepared adequately for the new flooding.

Again, there are worries that government officials will fail to meet the new challenges this year.

The heaviest rains in a century have forced hundreds of thousands of people to migrate to the city of Karachi, the largest city in Sindh, as well as Hyderabad. There are reports of thousands of people having contracted water-borne diseases as malaria and diarrhea.

A UN children's agency spokesman told media: We have assessed 16 out of 22 districts and roughly 1.8 million people have left their homes and 750,000 are living in temporary sites.”

Ironically, the southern Sindh province largely escaped the wrath of last year’s floods.

Ehsan Ali, a Pakistani who is living in a government camp in Hyderabad with his family, told a BBC correspondent: We had no advance warning of the floods. The breach took place within hours. First, we stayed put as everything we owned was there. But the water just kept on rising. Finally we had to flee. For several days we stayed out in the open before we made it here to Hyderabad.

Ali’s son is suffering.

It's diarrhea and fever, he said. “I've taken him to a doctor in town. They just distribute two tablets per person here at the camp.

Another refugee Abdul Hameed, a famer, complained to BBC about the government’s incompetence.

The government actions are just like the elephants in the old proverb: 'Different teeth for show and different for eating,' he said. They talk about all the money that's been spent but people like us have yet to see any of it. The government did provide us with some relief initially but that dried up in a month. Since then I have been working as a laborer in Hyderabad or as an aide for local NGOs that visit the camp. The government is nowhere to be seen. We don't even have basic medical care here.

Hameed added: As far as rehabilitation is concerned there has been none. The bigger landlords or politicians have used the funds to replenish their losses. Just look at my village. Only three families have returned after all this time.

Meanwhile, Karachi, Pakistan’s commercial capital has been paralyzed by the monstrous rains and flooding. Schools and markets have shut down and thousands of vehicles have been abandoned in submerged roads.

The UN estimates that 1-million houses in Sindh have been destroyed.