Nobody claimed responsibility for the attack but Taliban militants have attacked polio workers in the province in the past. More than 100 people have been killed in such attacks since December 2012.
Despite the attacks, Pakistan hopes to be removed from the list of polio-endemic countries by 2018 by achieving its goal of no fresh cases for a year.
Pakistan is one of only two countries in the world where polio, a crippling childhood disease, remains endemic. – AFP