At least one health worker was killed and two people injured on Saturday in an attack by gunmen on a polio vaccination centre in north-western Pakistan, police said, according to dpa. The attack targeted a government-run vaccination centre in the Peshawar, capital of the Khyber-Pakhtunkhwa province, police said. The Pakistan Tehreek-e-Insaf (PTI) party of former cricketer Imran Khan, which governs the province, had vowed to continue vaccinations despite threats by militants who say the measures against the crippling disease are un-Islamic. Policeman Ameer Khan said the two injured people were a medical worker and a woman patient. Insurgents frequently attack vaccination workers in Pakistan's tribal areas near the border with Afghanistan. Two policemen and a health worker were killed two weeks ago in two separate attacks on polio vaccination teams in the north-west. Polio is endemic in Pakistan, Afghanistan and Nigeria.