Pakistani officials say a bomb blast near the Afghan border has killed at least 35 people and wounded more than 60 others, in one of the deadliest attacks in the country's northwest in months.

Authorities say a remote-control bomb in a truck exploded in the Khyber tribal agency on Tuesday. The blast struck near a bus terminal in the town of Jamrud, destroying several vehicles parked near a fuel pump.

There was no immediate claim of responsibility. But some officials said the attack targeted members of the Zakhakhel tribe, which has formed a militia to fight against the Taliban in the region.

Since 2007, Islamist militants — some with links to al-Qaida — have carried out hundreds of bombings targeting members of pro-government militias and security forces.

Tuesday's bombing was the deadliest attack in Pakistan's northwest since last September, when a suicide bomber killed at least 31 people at a funeral for a tribal elder opposed to the Pakistani Taliban.

Pakistan's army supports the formation of local anti-Taliban militias, known as “lashkars.”

The Pakistani military has carried out offensives against militants in Khyber and the surrounding tribal agencies for more than four years.

United Nations Secretary-General Ban Ki-moon condemned Tuesday's bombing in Jamrud and reiterated the U.N.'s solidarity with Pakistan as it continues efforts to confront terrorism and extremism.

The U.S. Embassy in Islamabad said extremists who target innocent people and perpetrate such attacks show their “contempt for the value of human life.”