An Afghan group opposed to Taliban rule on Sunday rejected the police’s accusation that its members had killed polio vaccinators on a campaign to eradicate the crippling virus. Police had said two members of the National Resistance Front (NRF) had been arrested in connection with killing seven vaccinators on 24 February in the northern province of Kunduz. The NRF were the last group to hold out against the Taliban takeover last year, retreating to the Panjshir Valley, which eventually fell in September, weeks after the former government forces capitulated. The health workers were killed in sep…