Just moments before the explosion, an Assocaited Press reporter passed by the scene and saw more than 20 security forces gathered in the vicinity. After the blast, a traffic intersection in the area was splattered with blood. Body parts were scattered as far as 50 yards from the scene. Shattered glass also covered the area, which police cordoned off. Rana Akbar Hayat, a senior government official, said more than 10 people were killed.

"All are police officials," Hayat told reporters near the scene. ``It was targeted to the forces by the suicider." The blast came as thousands of Islamists were gathered not far away to mark the one-year anniversary of a deadly military crackdown on the radical Red Mosque. It was not clear whether the events were linked.

The explosion also came following recent threats of revenge from militants in Pakistan angered by a paramilitary operation against insurgents in the tribal North West Frontier Province. In June, a suicide car bomber killed at least six people near the Danish embassy in Islamabad. A statement attributed to Al Qaeda took responsibility for that blast, which was believed to have targeted Denmark over the publication of cartoons depicting Prophet Muhammad.

Violence levels have fallen in Pakistan since last year, but attacks still occur. The newly elected coalition government that came to power following the February elections has sought to end militancy in the country primarily through peace deals with extremists.