KARACHI: Three more anti-polio workers — a young man and two women — were killed in Karachi on Tuesday in an armed attack that came as a grim reminder of a brutal trend which had claimed four lives in December 2012.

The consistent terror and government’s failure to provide adequate security to the health campaigners triggered anger among volunteers across the country and left the authorities with no option but to suspend polio vaccination in the metropolis.

Gunmen killed the three workers and injured a woman vaccinator and a passerby in Qayyumabad area on the second day of an anti-polio campaign.

Officials believe the attack was carried out by militants.

The incident prompted the Sindh health authorities to suspend the campaign, while the lady health workers’ association announced its boycott till adequate security was provided to them.

Both police and health officials considered Qayyumabad as a safe area as far as polio campaign was concerned as the earlier killings of four workers had taken place in militancy-infested localities on outskirts of the city.

According to Korangi Industrial Area police, the polio workers were busy in their campaign in Qayyumabad’s A-Area when four men on two motorcycles opened fire on them and fled.

The bodies and the injured were taken to the Jinnah Postgraduate Medical Centre.

According to Dr Seemin Jamali, head of the hospital’s emergency department, the deceased -- Akbari, Anita and Fahad Khaleel -- were aged between 25 and 30 years. Polio worker Salma was admitted with bullet wounds on her chest and shoulder and her health was improving, the doctor said. An old man, Syed Asghar Ali Shah, was also injured.

Police said the polio team was without security at the time of the attack. “It had been agreed at the highest level that the polio workers would not move without security,” Karachi East DIG Munir Ahmed Shaikh said.He said there were 45 polio teams in the locality, of whom five were not accompanied by security personnel. Two teams had left to undertake the campaign when they were attacked.

Two of the attackers were wearing helmets.

The official said two localities of Korangi -- Bilal Colony and Mehran Town -- had been declared as sensitive for the campaign and police force, led by a DSP, had been deployed there.

Sindh Health Secretary Iqbal Hussain told reporters that about 50 areas in Karachi had been declared sensitive.

He said the campaign would be resumed after reviewing security arrangements.

Khairunnisa Memon, provincial chief of the All Pakistan Lady Health Workers, said they had decided to boycott the polio campaign till sufficient security was provided to them.

A police official said the previous attacks on polio workers in the city over the past two years had been carried out by militants.

Nisar Ahmad Khan added from Mansehra: A polio worker was gunned down in Shergar area when he was administering vaccine to children.

“But it is not an act of terrorism because preliminary investigation showed that it is an outcome of personal vendetta,” Mansehra Deputy Commissioner Zulfiqar Shah said.

According to witnesses, Mohammad Haleem, a schoolteacher, was administering vaccine along with his supervisor Munir Hussain in Butt Karal area of Oghi tehsil when Mohammad Afzal shot him dead and fled.

In reply to a question, the official said as more than 850 mobile teams were administering the vaccine in the district, each one of them could not be provided police security.

District Anti-Polio Campaign Supervisor Tariq Hussain said the killer was a relative of the victim, but the case would be investigated.