An Afghan official says a bomb has killed four Taliban insurgents, including a senior leader, in the country's eastern Nangarhar province.
No one immediately claimed responsibility for the bombing, which took place on Thursday.
Militants from the Islamic State group have targeted the Taliban in the past in eastern Afghanistan, where they have gained a foothold, including in a devastating bombing during a recent three-day truce that killed several Taliban fighters and members of the security forces during a temporary cease-fire.
Afghan defense ministry spokesman Mohammad Radmanish said on Thursday that a suspected U.S. drone strike in northeastern Kunar province killed a senior Pakistan Taliban commander and his two bodyguards.
Radmanish says the attack took place on Tuesday morning, near the border with Pakistan.