Campaigning in Pakistan ahead of today's general election has ended, with candidates holding final rallies.
The election will mark the country's first successful transition from one civilian government to another in its 66-year history.
However, the run-up to the election has been marred by violence.
At least 130 people have been killed in attacks on candidates and party workers since the beginning of April.
Yesterday, a motorbike bomb killed four people and wounded 15 close to offices of different parties in the main town of North Waziristan, the premier stronghold of the Taliban and al-Qaeda-linked groups on the Afghan border.
Security officials said PML-N, PTI and right-wing religious party Jamiat Ulema-e-Islam, an ally of the outgoing government, had offices nearby, reports AFP.
No one has claimed responsibility, and it was unclear exactly which candidates were targeted since several have offices in the block where the explosions occurred.
Also yesterday, unknown assailants threw a grenade at the main office of the secular Pakistan People's Party in Quetta, the capital of southwest Baluchistan province, wounding five people, said police spokesman Fayyaz Sumbal.
Baluchistan is home to both Islamic militants and separatist insurgents who want to break away from Pakistan, reports AP. The separatists have been staging attacks against candidates and party workers in an attempt to hamper today's election.
On Thursday, the son of former Prime Minister Yusuf Raza Gilani was seized during an election rally.
Ali Haider - a candidate for the Pakistan Peoples' Party (PPP) - was seized in the central city of Multan, Gilani said.
The end of campaigning was marked with emotional pleas by some candidates.
Nawaz Sharif, who leads the opposition Pakistan Muslim League-N (PML-N) and is tipped to be Pakistan's next prime minister, made an impassioned plea to crowds in Lahore just minutes before midnight on Thursday.
"If you give us five years you will see that we can change the fate of this country," he said.
He accused his opponents of selling the nation's honour and vowed that his party would be different, reports BBC.
Former international cricketer Imran Khan, leader of the Movement for Justice party, addressed supporters in the capital Islamabad by video link from a hospital bed.
He was injured after falling from a makeshift lift at an election rally earlier this week.
"God will not take me from this world until a new Pakistan is built," he said.
On the outskirts of Islamabad, supporters of the Pakistan People's Party (PPP) also held a large rally.
Party chairman Bilawal Zardari Bhutto, son of assassinated Prime Minister Benazir Bhutto and current President Asif Ali Zardari, also addressed the rally by video link.
"Benazir gave her life for this nation, for this country, for the people, for democracy, and for the completion of this struggle," he said.
"And my father, the President of Pakistan Asif Ali Zardari, who spent ten years in jail, and always said we should put Pakistan first. Now this is our duty to complete this promise."