Pakistan's principal Taliban group, the TTP, claimed responsibility for decapitating 23 paramilitary border guards, an act that on Monday caused peace talks to collapse.
The Taliban of the Mohmand tribal region reported in a communique Sunday the slaying of 23 Frontier Corps troops they had held captive since 2010, and said it was done to avenge the insurgents who have been killed in police custody.
In June 2012, the Taliban perpetrated a similar act when they decapitated more than a dozen soldiers they had captured in combat.
The TTP action was slammed by Pakistani Prime Minister Nawaz Sharif.
"Pakistan cannot afford such a bloodshed," he said. "We sincerely initiated the negotiation process as per recommendations of the All Parties Conference, but whenever we reach an encouraging point, the process has been sabotaged."
The decapitation of the soldiers sparked suspension of the meeting planned for Monday between government and insurgency envoys for the roundtable negotiations that began 11 days ago.
The government delegates' spokesman Irfan Siddiqui said in a communique sent Monday at noon that such actions harm the peace dialogue and that his team will meet again Tuesday to analyze the situation.
From the beginning, the formal peace talks in Pakistan have been immersed in controversy due to the insurgency stepping up its aggression despite its apparent efforts to negotiate.
Last Friday the TTP claimed a suicide attack against a police van that took the lives of 13 agents in Karachi.
Over the past two weeks about 50 people have been killed in armed attacks that have either been claimed by the TTP or had signs of being carried out by radical Islamists allied to that group.