GENEVA—Nearly 400 civilians have been killed in attacks in Afghanistan since the Taliban takeover, more than 80 percent of them by a group affiliated to ISIS, a U.N. report shows, underscoring the scale of the insurgency faced by the new rulers. It is the first major human rights report since the terrorist group Taliban seized power from the former U.S.-backed government in August. It covers the period from August 2021 to the end of February and said that 397 civilians were killed mostly in a series of attacks by ISIS-K. More than 50 people with suspected ties to ISIS-K had been killed in the same period, it said, with some tortured and beheaded and cast by the roadside. “The human rights situation for many Afghans is of profound concern,” said Michelle Bachelet, High Commissioner for Human Rights, in a speech introducing the report to the top rights body in Geneva. …