JALALABAD, Afghanistan's hard-line Taliban movement is engaged in vigorous fighting to prevent rival Islamic State (IS) militants from taking over remote villages it has long controlled.
The expanding fighting between the two jihadist organizations in eastern Afghanistan, however, is exposing impoverished villages to new atrocities.
Residents of the many remote Nangarhar districts say extremist militants are torturing and killing them as part of a war strategy to deny their enemies any advantage in the three-month-old fighting over the region bordering Pakistan.
"They [IS and the Taliban] have attempted every method of killing innocent people by horrific means [to spread fear]," a Nangarhar resident, who requested anonymity because of fear, told Radio Free Afghanistan. "They have blown people into pieces and have slaughtered people -- sometimes by tearing up their bellies to deliver a slow and painful death."
He says some civilians recently kidnapped by IS militants tell stories of horrific ordeals in captivity. "Boiling water was poured on many to force them to confess to crimes they had never committed," he said.
A video released by IS on August 8 showed its militants blowing up eight bound and blindfolded Afghan prisons with explosives.
The video appears to have been shot in the remote regions of Nangarhar where the IS militants began a campaign to replace the Taliban in May.
It shows prisoners confessing to working with the Taliban and the Afghan government. IS declared them as "apostates" to justify their killings.
But a resident of Achin district, where the killings took place earlier this month, says the victims were innocent civilians.
"They were either shepherds or engaged in selling wood in remote mountainous villages," he told Radio Free Afghanistan on the condition of anonymity. "We would not have shed tears if IS would really go after Taliban members, but we strongly resent the way these prisoners were blown up. IS has even deprived their families of giving them a decent burial."
Achin is one of the nine Nangarhar districts where the Taliban and IS have clashed in recent months. Government forces are also engaged in sporadic forays against the militants.
In a strongly worded statement last week, the Taliban condemned the IS video and said the victims were civilians.
"A horrific video … [showing] kidnappers who associate themselves with Daesh (the Arabic name for IS) brutally martyring several white-bearded tribal elders and villagers with explosives," a Taliban statement issued on August 11 said.
The Taliban said the executions were an "un-Islamic act [that] can never be justified. … No law can ever allow prisoners to be mistreated in such a manner."
Nangarhar's residents, however, accuse the Taliban of committing similar atrocities. In a video distributed in the province last month, purported Taliban militants are shown slaughtering four men in Haska Maina district. Insurgents accused them of spying for the government.
Fighting in Nangarhar has forced thousands of families to flee to Jalalabad to escape insurgent atrocities.
"The real problem is that both the Taliban and the IS are terrorizing civilians," Nangarhar Governor Salim Khan Kunduzi told Radio Free Afghanistan. "We know this is a major problem, and we are doing our best to address this because this is our duty."
Civilians in the region, however, are bracing for more violence. A succession struggle within the Taliban after the announcement of the death of founding leader Mullah Mohammad Omar last month is expected to prompt many defections to IS, which is keen on attracting seasoned fighters to its ranks.
Abubakar Siddique wrote this story based on Shah Mahmood Shinwari's reporting from Jalalabad, Afghanistan.