LAHORE: Police arrested three men for beating up two polio vaccinators in Lahore, officials said Friday, the latest case of violence against health workers seeking to immunise children against the crippling disease.

A scuffle broke out when two polio vaccinators visited the family's home for a second time Thursday to double check that they hadn't missed any children out of the polio immunisation campaign. The health workers and the men of the house got into a fight after the family said there were no children at home, a local police official said.

Police officer Mohammad Kamran said that police arrested three men on the complaint of the polio vaccinators after about 60 health workers held a protest outside the police station.

The three men – from the low-income Siddique Colony neighbourhood of Lahore – were arrested but later released on bail.

“Since beating someone is a bailable offence, the trio was released on bail later,” Kamran told AFP.

Mohammad Usman, the supervisor of the vaccination team, told AFP that the men became irritated because the health workers knocked on their door twice in the same day when there weren't any children in the house.

The vaccinators always visit homes a second time to be sure they haven't missed children who need to be immunised, Usam added.

Gunmen on Wednesday killed four members of a polio vaccination team in the outskirts of Quetta, the capital of southwestern Balochistan province.

Read: Jundullah claims attack on polio workers in Quetta

Pakistan is one of only three countries where polio remains endemic.

Attempts to stamp it out have been badly hit by opposition from militants and attacks on immunisation teams, which have claimed more than 60 lives in the last two years.

The militants have in the past claimed that the polio vaccination is a cover for espionage or a Western conspiracy to sterilise Muslims.

Officials say the number of polio cases recorded in Pakistan has reached 246 for the year – a 14-year high and more than double the total for the whole of 2013.

Among the new cases detected, 136 are in the troubled northwestern tribal areas at the border with Afghanistan, the stronghold of Taliban and Al Qaeda militants.