By Amjad Ali
ISLAMABAD (Reuters) - Pakistani Prime Minister Nawaz Sharif's party has consolidated its hold on power, results from by-elections released on Friday showed, cementing its ability to push through unpopular reforms aimed at kick-starting the stagnating economy.
Sharif began a third term as premier after the Pakistan Muslim League-Nawaz party won a landslide victory in national polls in May. He has since been attempting to stamp his authority on a nation long plagued by instability and violence.
The results showed his party won at least another five seats in the 15 by-elections held on Thursday, reinforcing its comfortable majority with at least 189 seats in the 342-seat National Assembly.
The by-elections on Thursday were held in seats that were forced to annul results from the May vote because of violence or because candidates had since vacated their seats, among other reasons.
The populist Pakistan Peoples' Party, which held power for five years before Sharif's victory, won three seats, with corruption a lingering concern among voters.
Pakistan Tehreek-e-Insaf, led by former cricket star Imran Khan, also won two seats after promising to crack down on graft.
The secular Awami National Party, which has frequently been attacked by the Taliban in their stronghold in Pakistan's often lawless northwest, also won one seat.
Turnout from the polling was generally lower than the May vote, Pakistani media reported, and several areas reported problems.
In Peshawar, the High Court intervened to stop vote counting in two areas and ordered polls to be held again amid reports that elders had prevented women from voting.
Another poll was postponed amid security fears in the town of Dera Ismail Khan, where a militant raid on a jail freed 250 prisoners last month.
In the financial center of Karachi, a roadside bomb aimed at a military vehicle on election duty on Thursday killed a soldier and a civilian, as well as wounding 20 people, said Seemin Jamali, a doctor from the Jinnah medical center.
The Pakistani Taliban claimed responsibility for the attack, saying it was their response to the government's offer of peace talks if the militants put down their arms.
"We wanted to convey a message to ... Nawaz Sharif that we would never lay down arms for the sake of meaningless talks and today's attack was to prove that we can strike wherever we wish," Taliban spokesman Shahidullah Shahid said.
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(Additional reporting by Jibran Ahmad in PESHAWAR and Syed Raza Hassan in KARACHI; Editing by Katharine Houreld and Paul Tait)