Two polio vaccinators were beaten up Friday in Pakistan's Sindh province.
According to officials, unknown attackers in Khairpur district beat up the members of the polio vaccine team with sticks, Dawn Online reported.
Last week, four new polio cases were reported in Khyber Pakhtunkhwa and North Waziristan.
The number of polio cases detected in Pakistan this year has risen to 88.
An official from the ministry of national health services said the only way to curb the disease was to announce a "polio emergency".
"After the proclamation of a polio emergency, vaccine refusal should be declared a crime," the official said.
An estimated 160,000 children have not been vaccinated since the Taliban banned immunisation in November 2012.