ISLAMABAD (Deutsche Presse-Agentur) -- Three people have died at relief camps for Pakistan's flood victims as diseases started to spread, media and health officials said on Tuesday.

Relief workers are scrambling to get aid to some 20 million people affected by the worst floods the country has ever faced, but the process has been hampered by the large numbers of victims.

A 4-year-old boy died of the water-borne disease gastroenteritis at a relief camp in the southern port city of Karachi, health officials were quoted as saying by the Dawn newspaper. Another 6-day-old baby died of tetanus.

Medical officer Khalid Ansari told the newspaper that the medical team had diagnosed 400 people in the camp with high fever and gastroenteritis -- most of them women, children and elderly people. Skin diseases were also very common, he added.

Officials said a 17-year-old girl died of gastroenteritis at the district hospital in Rajanpur, a city in the central province of Punjab, which has been hard-hit by the floods.

The UN said on Monday that 3.5 million children were at risk from water-borne diseases in Pakistan and urged the world community to urgently provide 460 million dollars required for emergency assistance.

Hundreds of thousands of people have been in the open for more than 10 days, as government-established relief camps have become overcrowded.

Even inside the camps the situation is deteriorating with people complaining of food shortages. Flood victims held protests in two cities in Punjab and Sindh province. Three people were injured when the police charged with batons to disperse demonstrators who had blocked a main highway.

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