Islamabad , Pakistan ( CNN ) -- The Taliban claimed responsibility Monday for two explosions targeting a government building in Pakistan 's tribal region , a Taliban leader said . The blasts killed 50 people and injured at least 70 others , according to Shamas Ul Islam , a senior government official in Mohmand Agency . Umar Khalid , head of the Pakistani Taliban in Mohmand Agency , said pamphlets had been distributed in the area 20 days ago warning members of peace committees or Lashkars ( tribal militias ) to abandon any efforts to join the government in fighting militants or face `` consequences . '' `` We will continue to attack all pro-government officials and their supporters who try to join any peace committees or Lashkars , '' Khalid said . The blasts occurred as government officials were about to meet with members of a volunteer militia group established to fight militants in the area , said Maqsood Amin , another senior government official in Mohmand Agency . Among those killed in the blasts was Haji Kachkol Khan , a senior leader of the peace committeee , Islam said . Amin said two suicide bombers were responsible for the blasts . One detonated inside the building and another outside the building 's gate , he said . The explosions occurred in the agency 's headquarters of Ghalanai , Pakistan . A curfew has been imposed in Ghalanai as a preventive measure , Islam said . The victims were taken to a local hospital after the blast , said Mohammad Zafar , a senior medical officer . Monday 's attacks were not the first time anti-Taliban and pro-government militias have been targeted in Pakistan . The attacks have been increasing over the past year , but Monday 's was one of the deadliest attacks this year . A November 5 suicide attack targeting a mosque in Dera Adam Khel , where locals had formed an anti-Taliban militia , killed 67 people . In July , another suicide attack killed more than 100 people , also in Mohmand Agency . Mohmand is one of seven semi-autonomous tribal agencies along the 1,500-mile border that Pakistan shares with Afghanistan . The Pakistani military has been battling insurgents in the area for some time . The attacks underscore that when locals decide to take a stand against the Taliban , there are sometimes deadly consequences . The Taliban usually warns locals against taking such actions , as they did in Monday 's attacks . The Pakistani government has said that such suicide attacks are a sign that the Taliban is growing desperate and becoming more aware that Pakistanis are taking a stand against them . In a statement , the U.S. Embassy in Pakistan condemned the attacks . `` While details of these suicide attacks are still being verified , it is clear this vicious crime killed and wounded many innocent people , '' the statement said . `` Our thoughts and sympathies are with the individuals and families affected by these inhumane acts . '' CNN 's Samson Desta and Reza Sayah and journalists Nasir Habib and Nasir Dawar contributed to this report .
NEW : Death toll at 50 , more than 70 people injured . Taliban claim responsibility for blasts . The blast goes off before a meeting between officials and a volunteer militia . It occurs in Mohmand Agency in the country 's tribal region .