Sunday's attack was the deadliest since a new Pakistani government came to power in March and launched a peace initiative with Taliban militants in an attempt to root out Al Qaeda operatives from the tribal belt that borders Afghanistan. Pakistan has begun decreasing its troop numbers in parts of its border region and freeing Taliban prisoners.
On Friday, the militants freed the Pakistani ambassador to Afghanistan, Tariq Azizuddin, who had been held by the Pakistani Taliban for more than three months.
US officials have questioned making such deals with the Pakistan Taliban, pointing out that previous talks gave militants time to regroup, resulting in a rise in Taliban attacks on US and NATO troops in Afghanistan.
The Christian Science Monitor pointed out that according to the State Department's recently published annual terrorism report, suicide attacks in Pakistan had more than doubled to 887 last year because of terrorist regrouping during a 2006 cease-fire.
Sunday's attack came as Pakistani Prime Minister Yousuf Raza Gilani met President Bush at a World Economic Forum conference in Egypt, where Mr. Gilani said his government was committed to fighting terrorism.