Pakistan called on the international community to rush aid to some 1 million people left homeless by massive flooding amid forecasts Monday that still more rain would be dumped on the stricken areas in coming days.

Floods due to a cyclone and rain have left as many as 100 people dead in southwestern Pakistan, a senior relief official said Sunday, but unofficial estimates are considerably higher.

Some 500 people have died across the subcontinent — in Pakistan, India and Afghanistan — since the start of the monsoon season in early July.

Following a two-day tour of the flooded area Sunday, Pakistan Prime Minister Shaukat Aziz asked for relief and rehabilitation aid from foreign countries, international agencies and private donors.

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He said more helicopters would be added to army efforts to ferry food, medicine and other relief supplies to areas of Baluchistan province which was hit by Cyclone Yemyin last Tuesday.

The military said Pakistani and Chinese engineers had reopened the Karakoram Highway, which runs between the two countries. The road link was severed by heavy, rain-spawned landslides near the 15,528-foot Khunjrab Pass.

The flooding also has spread into adjacent Sindh province to the east, where some 20,000 people were rendered homeless in Shahdad Kot district after waters from a canal spilled over protective embankments, provincial relief commissioner Munir Ahmed said Monday.

Tariq Ayub, Baluchistan's home secretary, who is overseeing the flood relief operation, said many of the casualties occurred due to drowning and people getting trapped under the debris of their collapsing homes in 13 hardest-hit Baluchistan districts.

Among the dead were 42 people who drowned Saturday in a stream flooded by rains and waters from a breached dam in Khuzdar district, Ayub said.

He said more than 100 other people were missing in the area.

The state-run Pakistan Meteorological Department forecast "widespread heavy rains" and storms in both Sindh and Baluchistan over the next four days.

On June 23, storms left at least 228 people dead in Karachi, the capital of Sindh.

In the Baluchistan city of Turbat, one of the worst-affected areas, doctors reported an influx of patients, many of them children, suffering from nausea, diarrhea and other water-borne diseases.

"They are drinking contaminated water," said Abdul Qadir, one of the physicians.

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