KARACHI: Around 22,000 Pakistani children are at risk in Karachi after the World Health Organization suspended polio vaccinations over a spate of shootings, a UN official warned Thursday.

WHO, a partner in government efforts to eradicate the disease, suspended activities in part of Pakistan's largest city last month and has not yet been approved to take part in the next campaign due in September.

On July 17, a UN doctor from Ghana working on polio eradication and his driver were shot in Gadap town and three days later a local community worker who was part of the same campaign was shot dead in the same area.

"We had a successful campaign in Karachi until those attacks," said Elias Durry, senior WHO coordinator for polio vaccination in southern Sindh province.

The campaign targeted 2.2 million children in Karachi, but 22,000 children in Gadap town were not administered polio drops because of security fears, he added.

"We fear the children of Gadap could be in danger of polio if we cannot go to them during our next campaign in September," Durry said.

Maryam Yunus, WHO spokeswoman in Pakistan, said activities would remain suspended in the area until police gave the go-ahead.

Police said they were still investigating the July shootings.

"We are investigating the incidents and trying to ensure fail-safe security for health workers in the future," said Mohammad Sultan, a local police official.

Pakistan, Afghanistan and Nigeria are the only three countries where polio remains endemic.

But Mazhar Nisar, health education advisor at the prime minister's polio monitoring cell, told AFP that the number of cases was in decline.

"Pakistan is no longer the country with the highest number of polio cases. It was for the past two years consecutively. Now Nigeria is the country with the highest number of polio cases," he said.

He said that 27 polio cases had been reported so far this year, compared to 71 for the same period last year and 198 for the whole of 2011.

"But there is no reason for complacency and we have to work harder to achieve the goal of a polio-free Pakistan," he said.

In Pakistan's northwestern tribal areas, health officials said 240,000 children were also at risk after warlord Hafiz Gul Bahadur and the Pakistani Taliban banned vaccinations in protest at US drone strikes. AGENCIES