The UN humanitarian coordination office OCHA, said the deaths and injuries occurred during five separate attacks on health workers – the latest in a recent spate which saw three health workers killed in March during the national polio vaccination effort in Nangahar.

Earlier this month, humanitarian workers with the Halo Trust demining group, came under attack in northern Afghanistan,  where extremists from an ISIL affiliate killed ten and wounded more than a dozen, in what the UN Security Council described as an "atrocious and cowardly targeted attack".

The UN Resident and Humanitarian Coordinator in the country, Dr. Ramiz Alakbarov, said that he was “appalled by the brutality of these killings” on Tuesday, adding that “the senseless violence must stop”, urging Afghan authorities to bring those responsible to justice.

He said the national campaign which only began on Monday, aimed at reaching nearly 10 million under-fives, had been suspended in the eastern region. “Polio immunization campaigns are a vital an effective way to reach millions of children…Depriving children from an assurance of a healthy life, is inhumane.”

An attack on children

“The UN strongly condemns all attacks on health workers anywhere. The delivery of healthcare is impartial, and any attack against health workers and those who work to defend them, is an attack on the children, whose very lives they are trying to protect”, he added.

The UN extended deepest condolences to the families, friends and colleagues of those who lost their lives, wishing the injured a full recovery.

Tedros 'deeply saddened'

The head of the World Health Organization (WHO) Tedros Adhanom Ghebreyesus, tweeted that he was “deeply saddened” by the attacks, adding that “access to essential health service and immunization campaigns should be unimpeded so that communities can be protected.”

According to news reports, Afghanistan reported 56 new cases of polio last year. But officials have reported that only one wild polio virus case has been detected in the country since October last year.