PESHAWAR, Pakistan -- Six police officers providing security for a vaccination team, and a boy standing nearby, were killed when a bomb struck their vehicle Wednesday in the latest deadly attack on health workers and authorities trying to fight polio in Pakistan, officials said.
Seven others were injured in the attack in Charsadda, 15 miles outside the provincial capital of Peshawar in northwest Pakistan, where Taliban militants have deemed polio vaccinations a front for Western espionage and resorted to bombings and assassinations to stop the vaccine from being administered.
A day earlier, assailants gunned down three members of a polio vaccination team in the southern port city of Karachi.
The targeted killings have contributed to polio's stubborn presence in Pakistan, which is one of three countries worldwide, along with Afghanistan and Nigeria, where the disease has not been eradicated. World health officials last week declared neighboring India, which hasn't had a polio case in three years, free of the acute viral disease.
In insurgent-plagued Khyber Pakhtunkhwa province, which United Nations health officials say is one of the areas most at risk of the virus, a three-day polio immunization campaign was launched Tuesday, with officials saying it would reach around 5 million children.
Under a security plan for health workers announced by the provincial government, police accompany every vaccination team, which typically is made up of one man and one woman.
A senior police officer, Saeed Wazir, told reporters that a bomb was planted on a bicycle that was detonated by remote control as the vaccination team traveled through Charsadda's Serdheri Bazaar.
Officials said that six police constables and one boy standing nearby were killed.
Earlier this week, four polio cases were reported in the neighboring tribal area of North Waziristan, where the Pakistani Taliban, who have been waging an insurgency aimed at overthrowing the central government, have placed a ban on polio vaccinations.
They have said that they would allow the vaccines if there were a halt to drone strikes, typically carried out by the U.S. military against militants in the tribal belt.
Officials said the immunization ban had deprived around 170,000 children under the age of 5 in the volatile area. According to the World Health Organization, Pakistan had 91 new cases of polio in 2013, compared with 58 in 2012.
Following Wednesday's attack, provincial officials suspended the vaccination campaign in Charsadda district.
[Updated, 11:10 a.m. PST Jan. 22: In another attack Wednesday, gunmen fired on Pakistani police escorting a Spanish cyclist through a volatile province bordering Iran, killing six officers and wounding the Spaniard and nine other officers, the Associated Press reported, citing officials.
The shooting occurred about 45 miles from Quetta, the capital of Baluchistan province.
The provincial home secretary, Asadur Rehman Gilani, identified the Spaniard as Colorado Solana while the Spanish media identified him as Javier Colorado, the AP reported. A blog written by the Spaniard said he was cycling around the world and that he had been the victim of an attack in Pakistan.]