Every time Abdullah Shirzad passes a checkpoint of Isis fighters, he fears he is about to die.
The teacher begins reciting the Koran and praying the fanatics pledging allegiance to Abu Bakr al-Baghdadi, the self-declared caliph, will let him pass.
In the three years since jihadists loyal to Isis (Islamic State) first appeared in his native Nangarhar province, they have imposed an extremist ideology that brands the population as apostates who can be punished by death; jihadists so brutal locals say they make the Taliban seem lenient in comparison.
The people of Nangarhar find themselves caught between two brutal militant groups after the Taliban vowed to drive Isis, also known as Daesh, from this eastern corner of Afghanistan.
"There is extreme fear in the areas under the control of Daesh and even the areas lying adjacent to the Daesh," said Shirzad, using a false name to protect himself. "According to Daesh's interpretation of Islamic law, every government job holder and every businessman and trader is an apostate.
"Daesh has the right to kill them or to terrorise them to bring them to the right path."
In reality, the militants' disdain and suspicion extends further, to nearly everyone not in their ranks, he said. Only those who join their jihad are truly considered Muslims.
Isis, which shocked the world, proclaiming a caliphate in Iraq and Syria, first emerged in Afghanistan in 2015 as militants swarmed to the banner of the extremists. The Afghan branch has endured as the Middle East caliphate has been swept away.
Attracting defections from extremist groups such as the Pakistan Taliban, and foreign fighters, it built a stronghold in Nangarhar and parts of Kunar.
US-led counter-terrorism forces have failed to root out Isis. Beheadings and public executions have become the group's trademark, with no one spared - victims include the elderly.
Isis' reign has caused many to flee the rural districts they control for the provincial capital of Jalalabad.
Shirzad, from an Isis-controlled part of Khogyani, fled, swapping his school for temporary classrooms set up for fellow refugees. His job as a teacher made him particularly vulnerable. While Taliban restrictions on education, particularly for girls, were notorious, he said they paled in comparison with Isis. The Taliban would negotiate on issues such as access to teams of polio vaccinators, whereas Isis "shows zero tolerance".
Yet the city is limited refuge. The trade hub overseeing road freight to Pakistan is a relentless target for Isis suicide bombings.
"Daesh has infiltrated the cities of Afghanistan and many educated people are supporters of Isis in Afghanistan. This is strange phenomenon," said Ghulam Mohmand, a doctor, who also used a false name to protect himself.
While the Taliban has been more confident elsewhere - this week it spent three days fighting for Ghazni city and sent envoys to Uzbekistan - in Nangarhar it has failed to shift Isis.
Shirzad predicts that the clash between the two groups will be bloody and long.
"It is very much clear that both the militant groups are two sides of the same coin, both are involved in killing people, extorting money, kidnapping and other brutal crimes," he said. "Both militant groups are not good for the locals."