The Islamic State organization is starting to attract the attention of radicals in Pakistan and Afghanistan, long a cradle for Islamist militancy, unnerving authorities who fear a potential violent contagion.
Far from the militants' self-proclaimed "caliphate" in Iraq and Syria, the name of ISIS has cropped up several times in jihadi circles in recent weeks in Pakistan and Afghanistan, the historic homeland of the Taliban and Al-Qaeda.
Leaflets calling for support for ISIS were seen in parts of northwest Pakistan, and at least five Pakistani Taliban commanders and three lesser cadres from the Afghan Taliban have pledged their support.
Pro-ISIS slogans have appeared on walls in several cities in both countries and in Kabul University, where a number of students were arrested.
Militant, security and official sources questioned by AFP in recent weeks say these are local, individual initiatives, and at this stage ISIS has not established a presence in the region.
But the success of ISIS in the Middle East is unsettling many of those charged with keeping a lid on Afghanistan and Pakistan's myriad extremist groups.
"ISIS is becoming the major inspiration force for both violent and non-violent religious groups in the region," Pakistani security analyst Amir Rana told AFP.
Earlier this month Pakistan's National Counter Terrorism Agency wrote to a dozen government agencies warning them to be on their guard against the ISIS group.
"The successes of ISIS play a very dangerous, inspirational role in Pakistan, where more than 200 organizations are operational," the agency said.
The letter came as the Pakistani army fights a major offensive in insurgent bastions of the tribal northwest, which appears to be weakening its major enemies, the Tehreek-e-Taliban Pakistan (TTP) and allied Al-Qaeda fighters.
Following the army offensive, the TTP, a coalition of disparate militant groups, has fragmented into rival factions over recent weeks, fueling rumors the movement could be overtaken by ISIS.
The TTP say they broadly support both the ISIS jihadists and Al-Qaeda.
They also say they have sent 1,000 fighters in recent years to help the jihadi struggle in Syria, an estimate confirmed by a Pakistani government source, and plan to send 700 more.