Pakistani Taliban have detonated bombs at the campaign offices of two politicians in the country's north-west, police said, killing at least nine people in an escalation of attacks on secular, left-leaning political parties.
In first attack, on the outskirts of Kohat city, a bomb ripped through the office of Syed Noor Akbar, killing six and wounding 10 people, police official Mujtaba Hussain said.
A second bomb targeted a campaign office of another candidate, Nasir Khan Afridi, in the suburbs of Peshawar city. That attack killed three people and wounded 12, police official Saifur Rehman Khan said.
Both politicians, who were not in the offices at the time of the blasts, are running as independent candidates for national assembly seats to represent constituencies in Pakistan's lawless tribal areas, where scores of militant groups operate including some with links to al Qaida. The general elections will be held on May 11.
Pakistani Taliban spokesman Ahsanullah Ahsan claimed responsibility for both attacks, as well as two others against secular political parties in the southern port city of Karachi.
"We are against all politicians who are going to become part of any secular, democratic government," he said.
The Taliban previously announced a strategy to target three political parties, including the Awami National Party (ANP), the Muttahida Quami Movement (MQM) and the Pakistan People's Party (PPP). All three are perceived as liberal, having earned the Taliban's ire by opposing the insurgency and extremism during their time in the outgoing government.
The onslaught has forced many of the parties to change their campaign strategy and has raised questions about whether the vote can be considered valid if some mainstream parties cannot properly take part.
Such attacks have killed at least 28 people in just last four days.
One of the most serious attacks occurred on April 21, when a suicide bomber blew himself up outside a meeting of the ANP in the north-western city of Peshawar, killing 16 people. The Taliban said the target was Haroon Ahmad Bilour, whose father, a senior party leader, was killed in a suicide bombing in Peshawar. He escaped unscathed, but his uncle, suffered minor injuries.