Pakistan government officials' bus hit by bomb

Pakistani rescue workers check the wreckage of a bus carrying government employees which was destroyed in a bomb blast, killing and wounding dozens of people, in Peshawar, Sept. 27, 2013.

ISLAMABAD A powerful bomb ripped through a bus carrying junior government officials Friday in Pakistan's northern city of Peshawar, killing at least 18 people. Officials suspect the attack was carried out by the Taliban.

The attack came less than a week after a suicide bomb attack on a church in Peshawar killed at least 83 people -- most of them members of Pakistan's minority Christian community who were leaving Sunday morning mass.

A Pakistani intelligence official who is based in Peshawar told CBS News after Friday's attack that the bombing had the "finger prints of the Taliban all over it." The official, who spoke on condition of anonymity, did not elaborate on the evidence pointing to the group.

After Sunday's church attack, the same intelligence official told CBS News that Lashkar-e-Jhangvi, a hardline Islamic militant group with ties to the Taliban, was behind that blast. Later, other security officials said the attack may have been carried out by Jundullah, another Taliban-linked militant group based in the country.

Friday's attack came hours before Prime Minister Nawaz Sharif was to address the United Nations General Assembly in New York. Pakistani government officials expected Sharif would use the occasion to once again complain about the U.S. government's continued use of drone aircraft to target suspected militants in Pakistan's tribal region, along the Afghan border.

U.S. officials say the suspected militant sanctuaries targeted by the drones are routinely used by militants to regroup in between attacks against U.S.-led Western forces and Afghan troops across the border in Afghanistan.

On Friday, a senior Western diplomat in Islamabad told CBS News that the two attacks in Peshawar highlight the deteriorating security conditions across the country.

"There are many more casualties from these attacks than the number of people killed by the drones," he said, adding that, "rather than the drones provoking this unrest, there is an internal policy failure inside Pakistan."

Sharif recently presided over a gathering that was attended by leaders of Pakistan's key political parties, as well as Gen. Ashfaq Pervez Kayani, the army's chief of staff. The event resulted in an agreement which has allowed Sharif's government to formally begin negotiations with Taliban militants in order to end the conflict raging in parts of Pakistan.

The Western diplomat who spoke to CBS News said, however, that such negotiations are unlikely to succeed, given that the Taliban believe they have the upper hand right now.