The deaths in a suicide bombing at an election rally in Pakistan rose to 20 on Wednesday as Taliban terrorists claimed responsibility, officials said, in the first major attack ahead of July 25 polls.

A local leader of the Awami National Party (ANP), Haroon Bilour, was among those killed in the attack in the city of Peshawar late Tuesday, officials have confirmed. The party has been targeted by terrorists in the past over its vocal opposition to terror groups like the Taliban. The bombing came hours after the Pakistan military spokesman said there were security threats ahead of national elections.