While its recent attack on a 14-year-old girl in Pakistan brought international outrage, the Pakistani Taliban take credit for a long list of assaults on civilians and the military in the country's mostly ungoverned tribal area along the Afghan border.
The banned Islamist group, which has intimate links to the Afghan Taliban and al Qaeda, unabashedly confirmed it tried to kill teen activist Malala Yousufzai as she rode home from school in a van October 9.
But before that, the group, formally known as Tehrik-i-Taliban Pakistan (TTP), took the global spotlight when Faisal Shahzad, a Pakistani-American, attempted to detonate a car bomb in New York's Times Square in May 2010. The TTP took responsibility, and Shahzad testified that he had received training from them.
The following September, the U.S. State Department designated the TTP a Foreign Terrorist Organization.
Are they "the Taliban?"
They are not "the Taliban" that the U.S. forces have been at war with in Afghanistan, according to a Pakistani analyst. But that they adopted the name "Taliban" is no coincidence.
Formally known as Tehrik-i-Taliban Pakistan, the group is very closely linked with its namesake in Afghanistan as well as with al Qaeda. It shares its religious extremist ideology -- but is its own distinct group.
The TTP also has a different goal, but its tactics are the same, says Raza Rumi, director of policy and programs at the Jinnah Institute, a Pakistani think tank.
"Their primary target is the Pakistani state and its military," he says. "It resents the fact that it (Pakistan) has an alliance with the West, and it wants Sharia to be imposed in Pakistan."
Another terrorism analyst notes that "there is a shared heritage between the two groups."
"The Pakistani Taliban emerged as a power alongside the Taliban as a kind of network of support," says Matthew Henman of IHS Jane's Terrorism and Insurgency Centre.
During the Soviet occupation of Afghanistan, fighters from Pakistan crossed over the border to fight. They retained close relations with the Taliban after returning home, Rumi says.
There are other militant groups in Pakistan's tribal region not under the umbrella of the TTP, who support the Taliban but do not pursue Tehrik-i-Taliban's goals of replacing the Pakistani state with an Islamist one.
Where do the TTP's roots lie?
Pakistan's army began hunting various militant groups in the semi-autonomous regions along Pakistan's border with Afghanistan, known as the Federally Administered Tribal Areas (FATA), in 2002.
In reaction, militant "supporters of the Afghan Taliban in the tribal areas transitioned into a mainstream Taliban force of their own," according to the Council on Foreign Relations.
In 2007, like-minded militias in Pakistan's tribal region came together under the command of Baitullah Mehsud, who was killed in a U.S. drone strike in 2009.
As a result of its beginnings, Tehrik-i-Taliban are not a unified fighting force but a coordinated coalition of militias.
"Since its formation, the TTP have been dominated by one tribe," Henman says. "That is the Mehsud tribe." When Baitullah Mehsud died, factions competed for Tehrik-i-Taliban's leadership.
The militant groups control different regions within the tribal area and often have different agendas and political objectives. The factions don't always speak with one voice, although it is widely believed they now recognize Hakimullah Mehsud as their leader.
The TTP may have started in the tribal regions, but have since expanded their network.
They are "not just guys hiding in mountains or caves." They maintain loose factions spread out as far as Punjab province, Rumi explains.
"And they have also been joined by criminal gangs" to raise money through kidnappings and extortion. But the TTP have maintained the coalition nature of their roots, which leads to internal strife.
The TTP's opposition to the government and its allies, particularly the United States, has galvanized them beyond their differences.
"When (former president Gen. Pervez) Musharraf sided with the U.S. in 2001 after the 'you are either with us or against us' line from (then-President George W.) Bush, this is when the Taliban began to resent the military," Rumi says.