Bombs killed 15 people and wounded dozens more including an election candidate in Pakistan on Tuesday, raising to more than 100 the death toll from attacks on the campaign for Saturday's polls.
The attacks took place in the northwestern town of Hangu, a flashpoint for violence between Sunni and Shiite Muslims, and in the northwestern district of Dir, where Pakistani troops crushed a Taliban-led insurgency in 2009.
The election will mark a democratic milestone in a country ruled for half its history by the military. It will be the first time that a civilian government has served a full term and handed over to another at the ballot box.
But the Pakistani Taliban has condemned the polls as un-Islamic and directly threatened the main parties in the outgoing ruling coalition led by the Pakistan People's Party (PPP).
Twelve people were killed and more than 40 injured at Hangu when a suicide bomber targeted election candidate Syed Janan, said Musarrat Qadeem, information minister of Khyber Pakhtunkhwa province.
Authorities gave different accounts of whether the bomber had been on foot or riding a motorcycle.
"He blew himself up near the vehicle of Syed Janan. He (Janan) was injured but he is safe," said Abdul Hameed Khan, a senior government official in Hangu.
Also Tuesday a roadside bombing killed at least three people as the brother of a provincial assembly candidate for the PPP went door to door to canvass for votes in Dir, police said.
"It was a remote-controlled bomb, it went off when the brother of a provincial assembly candidate Zamin Khan was campaigning," police officer Mehtab Khan told AFP.
"One vehicle has been totally destroyed. I can see three bodies. It is not immediately clear how many people were in the vehicle," he said.
There was no immediate claim of responsibility for Tuesday's attacks.
They raise to 107 the number of people killed in attacks on politicians and political parties since April 11, according to an AFP tally.
Janan is seeking re-election to the Khyber Pakhtunkhwa provincial assembly and is standing for the right-wing Jamiat Ulema-e-Islam, a religious party in the outgoing national coalition.
He told AFP he had received injuries to his head and shoulder.
"I was on my election campaign and coming to my vehicle when the bomber blew himself up. I received some injuries but survived. Two of my guards were seriously wounded," Janan said.
A joint rally for two other candidates from the same faction of the party was bombed in the tribal district of Kurram on Monday, killing 23 people in the deadliest single attack on the campaign so far.
The Taliban claimed responsibility for Monday's attack, saying the target had been Munir Orakzai -- a lawmaker in the national assembly who was in 2008 elected as an independent but was allied to the outgoing government.
The Taliban have been blamed for killing thousands of Pakistanis in a domestic insurgency over the past six years.
Elections have been postponed in three constituencies where candidates have been killed. They are in the southwestern province of Baluchistan, in Pakistan's biggest city of Karachi and in the southern city of Hyderabad.
The national campaign race has been dominated by the centre-right -- opposition leader Nawaz Sharif, head of the Pakistan Muslim League-N, and cricket star Imran Khan, looking to make a breakthrough for his Pakistan Tehreek-e-Insaf party.