KABUL  — Pakistan has arrested two people in connection with last year’s assassination of a former Afghan president who was trying to broker peace with the Taliban, two Afghan government officials said Friday.The officials said the two were detained in Quetta. The police chief in Quetta and the spokesman for the Frontier Corps said they had not heard of the alleged arrests. Pakistani foreign and interior ministries did not immediately answer phone calls seeking comment.One of the two Afghan officials, who spoke on condition of anonymity to discuss the sensitive case, said two individuals were arrested in Quetta last week. The other official said the two were on the list of possible suspects handed to Pakistani authorities last year.Pakistan’s relations with Afghanistan soured after the assassination of Burhanuddin Rabbani, a former Afghan president and head of the government-appointed peace council. Rabbani was killed Sept 20, 2011 in his home in Kabul by a suicide bomber posing as a peace emissary from the Taliban.The assassin, who hid explosives in his turban, gained entry to the former president’s home by convincing officials, including Karzai’s advisers, that he represented the Taliban leadership and wanted to discuss reconciliation.No one has claimed responsibility for the killing, and Taliban spokesmen have declined to discuss it.In a separate development, Afghan officials and the U.S.-led coalition were investigating an airstrike that Karzai said killed eight civilians in Kapisa province in eastern Afghanistan.Civilian casualties have caused serious tensions between the Afghan government and NATO.The coalition confirmed only that there was a “situation in Najrab district” of Kapisa province that was being assessed. More information would be released when the assessment is completed, the coalition said in a statement.A delegation of high-ranking officials appointed by Karzai travelled to Kapisa province on Friday to collect information.Hussain Khan Sanjani, the leader of the Kapisa provincial council, said seven of the victims were children, aged between 6 and 12 years. The eighth victim was an 18-year-old mentally ill man who was with the children.Sanjani, who visited the area on Thursday, said residents told him that coalition aircraft were patrolling overhead as coalition forces searched homes.Fearing the presence of coalition forces, the victims rounded up sheep and cows and moved them toward a mountainous area behind their homes, he said. When they got cold, they gathered brush and lighted a fire to keep warm, he said. One airstrike hit a large boulder and the other struck the victims, who were badly burned, according to Sanjani, who said he took photographs of the victims.