Bombardment by the Pakistani army in Afghanistan's eastern Paktika province on Tuesday killed at least 46 people, most of whom were children and women, said the Afghan Taliban, vowing to retaliate against their neighbour.
The bombing occurred at four locations in Afghanistan, Deputy Spokesperson Hamdullah Fitrat said on Wednesday, adding that six people were also injured.
Pakistani government and military officials did not immediately respond to requests for comment.
"Afghanistan considers this brutal act a blatant violation of all international principles and an obvious act of aggression... The Islamic Emirate will not leave this cowardly act unanswered," said Enayatullah Khowrazmi, the spokesman for the Ministry of National Defense.
The neighbours share a strained relationship, with Pakistan saying that several of the militant attacks that have occurred in its country have been launched from Afghan soil - a charge Afghan Taliban denies.
Their relationship was further complicated in March when the Taliban accused Pakistan of carrying out two air strikes on its territory, killing five women and children.
Pakistan acknowledged at the time that it had conducted "intelligence-based anti-terrorist operations" in Afghanistan but did not specify the nature of the operations.
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