Gunmen shot and killed a police officer assigned to guard a polio vaccination team in Pakistan's volatile southwestern Balochistan Province on October 25, authorities said.
The vaccination team members escaped unharmed and the two assailants fled the scene on a motorcycle.
The attack occurred in Balochistan's Pishin district, senior police officer Ghulam Asghar said.
The shooting came on the second day of a nationwide anti-polio campaign -- the fifth this year -- aimed at making Pakistan a polio-free state.
No group immediately claimed responsibility for the attack.
Islamic militants often target polio vaccination teams and police assigned to protect them, falsely claiming that the vaccination campaigns are a Western conspiracy to sterilize children.
Since April, Pakistan has registered 20 new polio cases and the outbreak has been seen as a blow to the country’s efforts to eradicate the disease, which can cause severe paralysis in children.
Pakistan and neighboring Afghanistan are the only countries in the world where the polio virus still exists.