Updated

The death toll from a homicide bombing that targeted Pakistan's top security official rose to 28 Sunday, the country's information minister said.

Interior Minister Aftab Khan Sherpao was left spattered in blood but only slightly injured in the attack Saturday in Charsadda, a town near his home village in North West Frontier Province.

There was no immediate claim of responsibility for the bombing, which took place just after Sherpao completed a speech to a rally of his political supporters.

But suspicion inevitably fell on Islamic militants who have repeatedly targeted top Pakistani officials, including President Gen. Pervez Musharraf, for supporting the U.S.-led war on terror.

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"It is a challenge to stop terrorism, and we are fighting it with full commitment," Information Minister Mohammed Ali Durrani said.

Hamid Karzai, the president of neighboring Afghanistan, sent a message of condolences and said long-suffering Afghans knew the hurt that Pakistanis were feeling.

Such attacks show the need for "strong cooperation between both countries to fight against terrorists and all those elements who try to bring instability to the region," Karzai's office said in a statement.

Karzai and Musharraf, who regularly accuse each other of failing to contain militancy, were to hold rare face-to-face talks Sunday in Turkey.

Pakistan has suffered a spate of homicide attacks this year, including attacks on the military and police, and on a five-star hotel in the capital, Islamabad. Officials have blamed militants, but have announced no clear results of their investigations.

Witnesses said Saturday's attacker got within 15 yards of Sherpao — detonating the bomb among a crowd that had gathered around the minister as he headed for his car to leave.

Sherpao expressed sorrow over the loss of life, but he later told reporters that such attacks "cannot deter my resolve in the fight against terrorism."

Officials initially said that 22 people were killed and 35 wounded.

By Sunday, the toll had risen to 28 dead and 52 injured, Durrani said. Police said most of victims were local residents, but also included several of Sherpao's police bodyguards.

Top officials have been targeted repeatedly since Pakistan became a Washington ally against Al Qaeda in late 2001.

In December 2003, President Gen. Pervez Musharraf narrowly escaped injury in two massive bombings 11 days apart in the garrison city of Rawalpindi. Some 17 other people were killed in the second bombing.

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