Like the PML-N, the PPP and several other parties have expressed serious concerns over the delay in the release of official results and the alleged expulsion of their polling agents from polling stations during counting of the votes for general elections 2018.
According to unofficial initial results, the PTI party is now leading in about113 national assembly seats, while PML-N is ahead in about 60seats, local media report.
"US Mission Pakistan is evaluating whether the conditions exist that would enable the participation of its election observers on Wednesday", the official said in response to a question.
PPP chairman Bilawal Bhutto is leading with 1,754 votes in NA-246 Lyari constituency, according to Samaa TV citing unofficial results.
Rights groups have warned that a rancorous election campaign and widespread allegations of manipulation imperil the wobbly transition to democratic rule and raise the spectre of bitter challenges of fraud after the election.
The polling for the general elections across Pakistan started at 8 am which will continue till 6 pm without any formal break.
"This is the most important election in Pakistan's history", Khan, 65, said after casting his vote in the capital, Islamabad.
It is thought the app stopped working around 6pm when polls closed and thousands of officials began trying to use the system at the same time.
At least 32 people were killed and several injured mostly in a suicide bombing in Balochistan on Wednesday as millions of voters queued up across Pakistan to elect a new government. "Unfortunately, Pakistanis have gone through so much violence that they are desensitized to it".
As well, Khan's vehicle was allowed to enter the polling station, and he also brought members of his party, the Pakistan Tehreek-e-Insaf, inside. PML-N's Amir Muqam is leading in NA-29 constituency. Sharif's party claims that their cadres were forced to stay at home which disenchanted their supporters to come out and cast their mandate.
Khan has been an outspoken critic of the US-led war in neighbouring Afghanistan as well as China's massive investment in Pakistan, which has racked up millions of dollars in debt to Beijing.
Jibran Nasir, an independent candidate from Pakistan's financial hub of Karachi, said he received death threats and even had a fatwa, or religious edict, issued against him after he refused to condemn Ahmadis, reviled by mainstream Muslims as heretics because they believe the messiah promised in Islam arrived over a century ago.
In Punjab Assembly, PML-N and PTI were in a neck-and-neck fight with both leading on 54 and 43 seats respectively according to trends available for 119 seats out of 297 seats.
There are 85,307 polling stations across Pakistan and more than 11,000 candidates are vying for 270 seats in parliament and 570 seats in four provincial assemblies.
Millions of voters turned out on Wednesday despite intense heat and a campaign marked by rancour, terrorist attacks, accusations of military meddling and the dramatic return of former prime minister Nawaz Sharif to serve a prison term for financial misdeeds. The form contains the final vote tally at each polling station.
The outcome could lead to a weak coalition government at a time when Pakistan urgently needs to address a foreign currency crisis and may need to go to the International Monetary Fund (IMF) for a second bailout in five years. "We know all the other candidates and parties".
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