Who are Jumaat-ur-Ahrar, the Pakistani Taliban group with links to Isis that killed 70 in Quetta?

The deaths of 70 people in the southwestern Pakistani city of Quetta in a Taliban attack on a government-run hospital has once more thrust Jumaat-ur-Ahrar, a splinter group of the Pakistani Taliban which at one point pledged allegiance to the Islamic State, back into the international spotlight. The suicide bomber detonated his explosive device, targeting a crowd of lawyers and journalists as they accompanied the body of a lawyer who had been killed earlier in the city, using tactics employed by the Islamic State throughout the Middle East.

Jumaat-ur-Ahrar or the "Gathering of the Free" has an ambiguous relationship with both the Pakistani Taliban, the Tehrik-i-Taliban, the group from which it split in 2014 and then rejoined in March 2015 and the Islamic State.

Despite the announcement by the group that it would be returning to join the Taliban, Jumaat-ur-Ahrar never disavowed IS. The tenuous links between Isis and the group showed when, in the aftermath of the Quetta attack, IS claimed responsibility for the slayings.

The extremist group, which expanded rapidly across Iraq and Syria in 2014, posted a message through it's propaganda outlet Amaq news agency saying its operatives had been responsible for the attack. "A martyr from the Islamic State detonated his explosive belt at a gathering of justice ministry employees and Pakistani policemen in the city of Quetta," the brief statement from the group read.

In September 2014 Jumaat-ur-Ahrar pledged allegiance to the Islamic State after a splinter in the Tehrik-i-Taliban formed over formal negotiations between the Taliban and the Pakistani government.

The efforts at dialogue meant that the hardline Jumaat-ur-Ahrar broke away under leader Omar Khalid Khorasani. The group was accused by the larger umbrella of the Taliban in Pakistan of deviating from its ideology. In response Jumaat-ur-Ahrar said it would not recongnise its leader Mullah Maulana Fazlullah.

Fazlullah ordered the killing of Malala Yousafzai in 2012 and masterminded the Peshawar school attack that killed 132 pupils in 2014.