Nangarhar is the deadliest Afghan province for US forces in the past year
Stars and Stripes, 8 January 2018
The Us daily quotes former AAN colleague Borhan Osman (still in his AAN capacity, it seems from earlier analysis) on ISKP in Nangrahar:
The group has established a command base in the Mamand and Peka valleys of Achin district, according to Borhan Osman, a researcher with the Afghan Analysts Network. Residents there told Osman that weapons and ammo are ferried into the rugged passes from just over the Pakistan border on the backs of mules.