ISLAMABAD, Feb. 7 -- The suicide attacker responsible for the deadly blast at a mosque in Islamabad's Tarlai area had returned to Pakistan from Afghanistan last year, Defence Minister Khawaja Asif said on Friday, as investigations into the attack intensified.

According to the minister, the attacker had travelled to Afghanistan around one-and-a-half to two years ago before returning to Pakistan, where he moved between several locations. At the time of the attack, he was reportedly staying in Nowshera, while his family members - said to hold extremist views - were traced to Peshawar.

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Khawaja Asif said that while the attacker appeared to be operating alone at present, ...