Mazar-I-Sharif, Afghanistan: Suspected Islamic State gunmen killed at least six Afghan employees of the International Committee of the Red Cross (ICRC) on Wednesday as they carried supplies in the north of the country to areas hit by deadly snow storms, government officials said.

Another two employees were unaccounted for after the attack in Jowzjan province, ICRC spokesman Thomas Glass said, but the aid group said it did not know who was responsible.

The aid workers were in a convoy carrying supplies to areas hit by avalanches when they were attacked by suspected Islamic State gunmen, Lotfullah Azizi, the Jowzjan provincial governor, told Reuters.

‘Daesh is very active in that area,’ he said, using an alternate name for Islamic State, which has made limited inroads in Afghanistan but has carried out increasingly deadly attacks.

Jawzjan police chief Rahmatullah Turkistani said the workers’ bodies had been brought to the provincial capital and a search operation launched to find the two missing ICRC employees.

Taliban spokesman Zabiullah Mujahid said his group was not involved in the attack and promised that Taliban members would ‘put all their efforts into finding the perpetrators’.

Last month, a Spanish ICRC employee was released less than a month after he was kidnapped by unidentified gunmen in northern Afghanistan.

That staff member was travelling with three Afghan colleagues between Mazar-i-Sharif and Kunduz on Dec. 19 when gunmen stopped the vehicles.

The other Afghan ICRC staff were immediately released.

In a recent summary of its work in Afghanistan last year, the ICRC said increasing insecurity had made it difficult to provide aid to many parts of the country.

‘Despite it all, the ICRC has remained true to its commitment to the people of Afghanistan, as it has throughout the last 30 years of its continuous presence in the country,’ the statement said.