The militants began their attacks after a Pakistani doctor provided crucial intelligence information to the U.S. prior to the U.S. military's assault on al-Qaeda leader Osama bin Laden's heavily guarded compound in Abbottabad. In the ensuring firefight, bin Laden was killed.
On Tuesday gunmen killed a female polio worker and wounded another in Kaggawala village on the outskirts of Peshawar in Pakistan's northwest.
The assault is the latest attack against international medical teams involved in attempting to eradicate polio in Pakistan. No group has claimed responsibility for the latest killings, Dawn newspaper reported Tuesday.
Pakistani President Asif Ali Zardari condemned the "cowardly" attacks, pledging that "the government will not permit militants to deprive our children of basic healthcare."
Pakistan is, along with Afghanistan and Nigeria, one of three countries where polio is rampant. A local official said that more than 600 teams are taking part in the latest campaign in Bajur to vaccinate 220,000 children.
Following the latest attack, more than 14 suspects were taken into custody by security forces.