PESHAWAR: Gunmen attacked a polio vaccination team in northwest Pakistan on Tuesday killing a health worker and two policemen -- the latest deaths in a dangerous campaign to eradicate the disease, reports AFP.

Pakistan is one of two countries, alongside neighbouring Afghanistan, where polio remains endemic, but where vaccination teams have been targeted by militants. 

"The victims died at the scene and the gunmen escaped."

The attack happened in North Waziristan, a region that borders Afghanistan and which was once a significant refuge for Afghan and Pakistan Taliban militants.

Shahid Ali Khan, a senior government official in the district, confirmed the incident.

Scores of polio workers and security officials guarding them have been killed in militant attacks since 2012.