At least six more people died of injuries on Tuesday bringing death toll from the bombing in Jamiat Ulema-e-Islam-Fazl (JUI-F) rally at Kurram Agency to 25 with over 80 people wounded.
Political administration said the bomb was placed near main stage of the venue of the rally. It exploded when Munir Orakzai, a former lawmaker and JUI-F candidate for NA-38, left the dais after addressing the meeting.
He remained unhurt in the blast claimed by Taliban.
The attack in the Kurram region, an ethnic Pashtun area near the Afghan border, will raise questions about whether the Taliban have expanded their campaign beyond secular parties.
Hospital administrator Inayatullah Khan said 25 people were killed in the blast and the death toll could rise because some victims were critically injured.