"The plan for today’s [Wednesday's] attack was drawn up by the Haqqani network with direct coordination and cooperation from Pakistan's Inter Services Intelligence (ISI)," the National Directorate of Security said in a statement late Wednesday.
The Haqqani network are a particularly brutal insurgency group which closely cooperates with the Taliban. Afghanistan has long accused Pakistan of supporting and sheltering Haqqani and Taliban elites and fighters.
More than 460 people were wounded in the bombing, which took place in the morning rush hour in an area full of foreign embassies and Afghan government institutions, including the presidential palace.
Public Health Ministry spokesman Mohammad Ismail Kawusi said the identification process of victims had resumed on Thursday.
However, "some bodies will probably never be found, they were torn to pieces", he told dpa, adding that some of the bodies were hardly identifiable.
There were also "some legs and hands, about 10 or 15" that could not be connected to victims already identified, he said, suggesting the number of dead could rise.
US President Trump offered his deepest condolences for the victims to Afghan President Ashraf Ghani in a phone call, "underscoring the barbaric nature of the terrorist who are enemies of all civilized peoples," according to a statement by the White House.
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