PESHAWAR, Pakistan (AP) -- Gunmen shot to death a policeman protecting a team of female polio workers in northwestern Pakistan on Wednesday, the latest in a series of attacks on people working on the U.N.-backed vaccination campaign, police said.
No group has claimed responsibility for the attacks but suspicion has fallen on Islamic militants. Some have voiced opposition to the campaign, accusing health workers of acting as spies for the United States and claiming the vaccine is intended to make Muslim children sterile.
Pakistan is one of only three countries in the world where polio is still endemic. Health workers have made progress in combatting the disease in recent years, but the attacks threaten to reverse that progress.
The attack on Wednesday occurred in the district of Mardan in Khyber Pakhtunkhwa province, said police officer Mohammed Nabi Khan. One policeman was killed and another wounded. No polio workers were harmed since they were inside a home giving polio drops to children at the time of the attack, said Khan.
In December, gunmen killed nine polio workers in different parts of Pakistan. Several more workers have been killed since then, as well as policemen who were protecting them.
The U.N. said last month that some 240,000 children missed vaccinations since July in parts of Pakistan's tribal region, the main sanctuary for Islamic militants, because of security concerns.
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