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ISLAMABAD: Pakistani investigators sifted through evidence on Monday in the wake of a suicide bombing that killed 15 people near a protest marking the anniversary of a bloody raid on the radical Red Mosque.
Police in white jumpsuits made fingertip searches through the night to find clues after Sunday's blast, which targeted a crowd of policemen guarding the rally by thousands of hardline Islamists in the Pakistani capital.
There was no immediate claim of responsibility but officials said they were examining a range of possible culprits, including the mosque's former students and Taliban militants based near the border with Afghanistan.
“We have assembled a team of senior policemen and officials from the (government's) Special Investigation Unit and they will meticulously probe this attack,” interior secretary Kamal Shah told AFP.
“At this stage it is too early to say who is behind it,” he added, confirming that 13 policemen and two civilians died in the blast.
Last year's operation against the mosque unleashed a wave of revenge suicide attacks that left around 1,000 people dead and pushed the newly-elected government into entering peace talks with Taliban militants.
Militants said to be loyal to the Red Mosque have been blamed for some of those attacks, especially a number of blasts in Islamabad, although most have been attributed to Pakistani Taliban rebels.
Sunday's demonstration saw religious students from across the country calling for US-backed President Pervez Musharraf to be publicly hanged for the siege and storming of the radical mosque, in which 100 people were killed.
The attack was strongly condemned by the United States .
“We offer our sincere condolences to those injured in this needless act of violence, and especially to those families who lost loved ones,” White House national security spokesman Gordon Johndroe said.
Pakistani security officials said they were focusing on the presence of some members of banned Islamic extremist groups, including Jaish-e-Mohammed and Sipah-e-Sihaba, at Sunday's rally to commemorate the 2007 raid.
“We have no firm leads but we are examining the possibility that some of these groups may have been involved or were in league with followers of Lal Masjid (Red Mosque),” a senior security official told AFP on condition of anonymity.
A spokesman for Pakistan's main umbrella organisation of Taliban militants, led by top commander Baitullah Mehsud, said he was not aware of any of the group's members having claimed responsibility.
“I am not in a position to indicate any claim of responsibility, I have not heard from any of our groups,” spokesman Maulvi Omar told AFP by telephone from an unknown location.
The bombing is likely to increase the pressure on the Pakistani government, which has come under fire from the United States and other Western allies with troops in Afghanistan over its negotiations with militants.
Pakistani forces launched an operation nine days ago against Islamic radicals near the northwestern city of Peshawar but the government has yet to convince its foreign backers it is serious about combating militancy.
Musharraf, whose political allies were trounced in elections in February by opposition parties including that of slain former premier Benazir Bhutto, warned on Friday that the government had to stop the spread of extremism.
