Pakistani security officials examine the site of a bomb blast in Jamrud on Tuesday. A remote-controlled bomb blast killed 35 people and wounded more than 60 others in the deadliest attack in months in the Taliban-hit tribal region of northwest Pakistan. (A. Majeed/AFP/Getty Images)

A bombing Tuesday morning killed 30 people in Pakistan’s volatile northwest, and officials said a pro-government militia was the likely target.

The blast tore through a bus station in the town of Jamrud in the Khyber tribal area, part of the semiautonomous border region that is home to the Taliban and other militant factions. The Pakistani army is battling insurgents in Khyber, as are members of the Zakakhel tribe, some of whom were waiting in a passenger pickup area when the bomb detonated.

Shakil Umerzai, a senior political official in Jamrud, said at least six tribal police officers were killed in the attack, the deadliest since a bombing targeting a different pro-government militia killed more than 45 people in September.

There was no immediate assertion of responsibility, but a local security official, who was not authorized to speak publicly, said the bombing bore the hallmarks of the Pakistani Taliban. The Pakistani military is believed to be conducting peace talks with the group, a splintered umbrella organization known as Tehrik-i-Taliban Pakistan, or TTP, but insurgents have continued to carry out attacks.

“The attack on pro-government tribesmen is part of the militant outfit TTP’s campaign to avenge the killing of TTP members in this agency recently,” the official said, referring to insurgent deaths during a military offensive.

Islamist militants in Pakistan’s tribal areas have been waging a fierce campaign of violence against the Pakistani state since 2007, and their prime targets have been security forces and tribal militias , or lashkars.

Although military operations and CIA drone strikes contributed to a drop in militant violence nationwide in 2011, attacks in the tribal areas and casualties among security forces rose, according to a recent report by the Pak Institute for Peace Studies, an independent research firm.

Last week, the Taliban killed 15 paramilitary soldiers whom its fighters had captured elsewhere in the tribal areas. On Monday, government officials said militants had killed 10 more paramilitary soldiers they had been holding captive.

Dozens of people at the Jamrud bus depot were injured in Tuesday’s blast, and the casualties included women and children, officials said.

“It is a highly condemnable act against innocent human beings,” said Malik Ismail Koki Khel, a tribal elder from the area. “We are in shock over this attack.”

Correspondent Karin Brulliard in Islamabad contributed to this report.