A bomb planted by Taliban insurgents ripped through a vehicle carrying Pakistani troops on Sunday (January 19), killing 20 soldiers and prompting Prime Minister Nawaz Sharif to cancel his trip to the World Economic Forum in the Swiss resort of Davos this week.
At least 30 others were wounded as the convoy prepared to leave the volatile north-western town of Bannu for nearby North Waziristan, a lawless, tribal region on the Afghan border where many al Qaeda-linked militant groups are holed up.
The bold, daylight attack - the biggest on the Pakistani security forces in months - dealt a major blow to the army at a time when Pakistan is already under strong U.S. pressure to do more to contain the insurgency on its western frontier.
The army said the bomb had been planted in a civilian vehicle rented locally in order to transport troops to North Waziristan.
The device exploded as soldiers got inside the car and prepared to leave.
Shahidullah Shahid, a spokesman for the Tehreek-e-Taliban Pakistan (TTP), claimed responsibility for the attack in a telephone call from an undisclosed location.
The blast, which was heard all around Bannu, took place despite the Taliban's recent hints they might be theoretically open to the idea of peace talks with the government.
In a video video recorded on Friday (January 17) and given to Reuters Television, a Taliban spokesman, Azam Tariq, said the Taliban had neither refused "dignified, serious and meaningful talks" in the past, nor had they denied the importance of negotiations, but the government had never made any serious effort to hold talks with them.
"The war in our tribal areas was started not by the Mujahideen, but by the Pakistani government, at the behest of America. Now, the ceasefire should also be announced by the government. It is also the responsibility of the government to make the atmosphere conducive for talks. When we see progress from their side in making the atmosphere favourable and peaceful, then God willing, we will also review our activities," Tariq said.
The group had earlier vowed to step up attacks on security forces after electing a new hardline leader, Mullah Fazlullah, at the end of last year.
But another Taliban spokesman, Shahidullah Shahid, denied the movement had decided to ditch talks altogether after the death of its previous leader, Hakimullah Mehsud, in a November drone strike which enraged the Taliban and hardened its stance on the government.
"The truth is that before the martyrdom of our Chief, we had said that if the government wants to negotiate, it has to prove that it is sincere, and also that it has the authority. After the martyrdom of the Chief, we did not refuse to talk because they had martyred him. There is a war going on between us and them, and in a war people get killed. They kill us, we kill them," Shahid said.
"We refused to talk because the drone attack that martyred the Chief proved that the government is neither sincere nor has the authority. Power rests in the hands of someone else. But, even now, if the government can prove its sincerity and its authority, we are ready for talks," he added.
Shahid denied the TTP had anything to do with an explosion that ripped through a packed Islamic preaching centre during evening prayers on Thursday (January 16).
At least seven people including an eight-year-old child were killed in the Islamic centre in Peshawar, a volatile city on the Pakistani border with Afghanistan. Around 70 people were wounded, officials said.
"We strongly condemn the attack on the Tableeghi centre, because we will not get good points for attacking them. Any attack on them would bring a bad name to our Movement. How can we carry out such activities and bring a bad name to ourselves?" Shahid said.
Prime Minister Nawaz Sharif condemned the attack and cancelled his trip to the Davos gathering which runs from Jan. 22 to 25 and draws thousands of the world's most influential people.
"Our nation is united against extremism and terrorism and the sacrifices rendered by our citizens and personnel of law enforcing agencies will not go in vain," he said in a statement.
Sharif came to power last year promising to step up efforts to engage the Taliban in peace talks and find a negotiated solution to years of fighting.
Even though both sides have made tentative overtures towards possible negotiations, no meaningful discussions have taken place for years. The Pakistani Taliban, who are loosely aligned with their Afghan namesakes, are also deeply fractured, making policy co-ordination all the more difficult within the group.