A probe into the deadliest attack on Pakistani troops waging a counterinsurgency campaign along the Afghan border was progressing well, an investigator said Thursday, as a previously unknown group claimed responsibility for the suicide bombing that killed 42 soldiers.
A man with explosives strapped to his body ran up to soldiers doing calisthenics and blew himself up on Wednesday at an army training center in the town of Dargai, about 100 kilometers (60 miles) north of Peshawar, the capital of North West Frontier Province.
At least 42 troops were killed and 20 wounded, some in critical condition.
"Body parts of the suicide bomber have been collected for DNA test," said a security official at the training center Thursday as soldiers readied for calisthenics.
"We have vital clues and the investigations are proceeding well," said the official who asked not to be named because of the sensitive nature of the case.
Suspicion immediately fell on pro-Taliban militants who vowed revenge for an airstrike on a Muslim boarding school last week that killed at least 80 people in the Bajur tribal region to the northwest.
The government claimed the school was being used to train pro-Taliban guerrillas, but local residents said almost all the victims were children or teenagers, reports AP.
Several hours after the suicide attack, an unidentified man telephoned Pakistani journalist Rahimullah Yousafzai in Peshawar and claimed responsibility.
The man said "Pakistani Taliban" carried out the bombing to avenge the Bajur incident. He identified the group's leader as Abu Kalim Mohammad Ansari.
Security officials said they were not familiar with either the group or its alleged leader.
The caller also claimed that 275 volunteers had offered to take part in suicide bombings following the Bajur attack, media reports said.