Health workers accused of being US spies London - Arabstoday The United Nations has suspended its polio eradication campaign in Pakistan after two more health workers were killed and another critically injured this Wednesday. A female health worker who was supervising the polio vaccinations, along with her driver, were killed in the northwestern Pakistani city of Charsadda. \"Three masked gunmen on a motorcycle opened fire on the health worker\'s car, killing the woman and her driver on the spot,\" senior police officer Zahir Shah told the media. A volunteer health worker was shot in the head few hours earlier while administering the oral vaccination in Peshawar. Hilal Ahmed, who is in his early 20s, is said to be in a critical condition. Earlier this week, five vaccination workers were killed by gunmen in the southern port city of Karachi, and another in Peshawar, which is the capital of the northwestern Khyber Pakhtunkhwa province bordering Afghanistan. The UN\'s World Health Organization (WHO) - which partnered with the Pakistani government in the anti-polio drive - said that the decision to suspend the campaign was made because of the \"very precarious\" security situation.