Militants targeted a polio vaccination team in northwestern Pakistan on Tuesday, killing a policeman in the latest attack on workers engaged in the campaign against the crippling disease.
The unidentified gunmen opened fire on the team at Latambar area in Karak district of Khyber- Pakthunkhwa province.
The policemen were providing security cover to the vaccinators.
A policeman patrolling the area was killed in the firing.
No group has claimed responsibility for the attack.
Pakistan and neighbouring Afghanistan are the only two remaining countries in the world where polio is endemic.
Immunisation efforts in the past have been hampered by militants. They have alleged the immunisation campaigns are a cover for Western spies.