PESHAWAR, Pakistan -- A deadly day of violence against Pakistani polio workers saw three killed, a further four shot and two more groups feared kidnapped, a World Health Organization official told NBC News.
Armed men gunned down one group in the Qayyum Abad area of Pakistan's biggest city Karachi as they worked to inoculate people against the potentially fatal disease, said the official, who did not wish to be named for fear of reprisals.
"Three members of the polio team, two of them women, died on the spot," the official added. "Four other people were shot and injured in the city."
Two other polio teams working in different areas of Karachi are missing and feared kidnapped, the official said, adding that the WHO was in touch with the local Sindh government in an effort to bring them to safety.
All of the teams were working as part of a United Nations health program to vaccinate the whole country against the highly infectious disease.
Polio, which was virtually eliminated from the Western hemisphere in the second half of the 20th century, affects the nerves in the muscles necessary for breathing, causing respiratory difficulty and paralysis of the arms and legs.
No groups claimed responsibility for the attacks or alleged kidnappings, but polio teams in Pakistan have faced serious security threats from militants after Pakistani physician Dr. Shakil Afridi conducted fake polio campaign in Abbottabad to help the CIA track Osama bin Laden in May 2011. Religious clerics have also claimed that vaccination is a Western ploy to render their males infertile.
In November last year, 11 schoolteachers were kidnapped in the Bara subdivision of the Khyber tribal region as they administered the vaccine. They were later released.
According to the World Health Organization, 24 polio workers were killed last year in attacks on vaccination teams.
Henry Austin reported from London.
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