PESHAWAR, Pakistan, July 10 (Reuters) – The death toll from a suicide attack in a volatile border region of Pakistan climbed to 102 on Saturday, showing the militants’ continued ability to stage deadly strikes despite losing ground in army offensives.

The Tehrik-e-Taliban Pakistan (TTP), or Taliban Movement of Pakistan, claimed responsibility for Friday’s attack in Mohmand, a Pashtun region on the northwestern border with Afghanistan, where security forces have stepped up operations against militants in recent months.

Friday’s attack is the deadliest Pakistan has suffered since an attack on a market in Peshawar in October last year that killed 105.

Five children, aged 5 to 10, and several women were among the dead, and the toll rose on Saturday as rescuers working throughout the night found more bodies in the rubble.

“We have recovered more bodies from the debris of dozens of shops that were razed to the ground by the blast and the number of dead has increased” to 102, said Rasool Khan, assistant political agent of Mohmand.

The bomber blew himself up outside Khan’s office. There were mixed reports that a car bomb was the source of a possible second blast.

Late on Friday, a TTP spokesman in Mohmand who identified himself as Ikramullah Mohmand, said anti-Taliban tribal elders from various peace committees who had come to Khan’s office were the target.

A senior elder and two others were killed in the attack.

Among nearly 80 wounded were several people displaced by fighting between security forces and militants, who were collecting relief goods near the blast side.

The latest militant attack underscored multiple security challenges facing nuclear-armed U.S. ally Pakistan, whose support is vital in attempts to stabilise neighbouring Afghanistan, where U.S.-led NATO troops are fighting a raging Taliban insurgency.

The military has made progress over the past year when they pushed militants out of the Swat valley, northwest of Islamabad. In October the army began an offensive in the militants’ South Waziristan bastion on the Afghan border.

The offensive was extended to Orakzai in March as many of the militants who fled the South Waziristan operation took refuge there and in Mohmand. Hundreds of militants have since been killed in air strikes in the two regions.

Troops killed 20 militants in an overnight clash in South Waziristan after insurgents attacked a military checkpost in their previous stronghold of Makeen, intelligence officials said. There was no independent confirmation of the casualties.

Despite losing ground in military offensives, militants have proven their ability to bounce back, responding with a barrage of bomb attacks in towns and cities, killing hundreds of people.

Two suicide bombers killed at least 42 people in an attack on Pakistan’s most important Sufi shrine in the eastern city of Lahore last week.

While praising Pakistan’s efforts to fight homegrown militants, the unabated violence is a source of worry for the United States, which also wants Islamabad to go after Afghan militants who cross the border to attack U.S. troops in Afghanistan.

In a separate incident in Afghanistan, suspected Taliban militants attacked a bus carrying Pakistani Shi’a tribesmen travelling from the Kurram tribal region and heading to Peshawar via Afghanistan, killing 11 and wounding one, residents and government officials said.

Pakistani tribesmen take a circuitous route through Afghanistan to travel between Kurram and Peshawar as the road linking the two regions is often closed because of militants and Pakistani Army operations. [ID:nSGE669GBL]

(Writing by Augustine Anthony; Editing by Chris Allbritton and Jeremy Laurence) (E-mail: augustine.anthony@thomsonreuters.com; Reuters Messaging: augustine.anthony.reuters.com@reuters.net; Islamabad newsroom: +92 51 281 0017)) (If you have a query or comment about this story, send an e-mail to news.feedback.asia@thomsonreuters.com)