Further details were not available and there was no confirmation from Daesh, whose local branch is known as Daesh in Khorasan, an old name for the area that includes modern Afghanistan.
Separately, a bomb exploded in Nangarhar’s capital, Jalalabad, the same day, killing at least eight people, although there was no indication of who may have been responsible.
Attaullah Khogyani, the provincial governor’s spokesman, said the 15 Daesh fighters were executed after a bout of infighting in the group, which has become notorious for its brutality. The killings occurred in the Surkh Ab bazaar of Achin district.
Nangarhar, where the movement first appeared around the beginning of 2015, is a volatile hub for Daesh and other militant groups on Afghanistan’s porous border with Pakistan.
The Taliban and Daesh have frequently fought each other in Nangarhar and both have been targeted by sustained US air strikes.
However the exact nature of the relationship between the two groups is little understood. There have been isolated incidents in Afghanistan in which the fighters from the two groups appear to have cooperated.
According to Afghan intelligence documents reviewed by Reuters earlier this year, security officials believe Daesh is present in nine provinces, from Nangarhar and Kunar in the east to Jawzjan, Faryab and Badakhshan in the north and Ghor in the central west.