PML-N Vice President Maryam Nawaz on Friday accused the PTI of seeking to rig the by-elections through vote theft.
Maryam released a series of "bombshell" videos as supposed proof of the claim.
She claimed that people from PTI were "caught red handed stealing bagfuls of votes". She said PML-N MPA Adil Chatta and Ataa Tarar were the ones to have caught the "culprit".
Maryam claimed the seal of the bag of votes was also broken and further accused the police of being "a part of the plan to steal votes for PTI".
She followed it up with videos showing the bag in question, with a PP-51 Gujranwala-I label.
Maryam also shared a video of a man sitting silently alongside a bag of votes. PML-N workers can be heard asking him where he was taking the bag of votes.
"We had sent him in along with the Rangers and he was taking this bag with him," a man says.
The man in a subsequent video was identified as a presiding officer and accused of stuffing the said bag with fake votes.
As her updates continued to roll in, Maryam shared another video of PML-N catching the presiding officer, reportedly belonging to Virtual University Polling Station Wazirabad, who she claimed was "running away with a polling bag, the seal of which was broken".
"He has been brought before the District Returning Officer," she said.
More videos followed, one of another man being nabbed by MPA Chatta, also accused of "stealing votes".
Maryam said that PML-N representatives are keeping watch over the guy "caught red handed" and "are not letting him go".
"Aise nahi chorrein ge. 2018 main ho gaya, ho gaya. Ab nahi Insha'Allah. (We won't let this go as easily. Whatever happened in 2018, happened. Not anymore, God willing)," she wrote.
The PML-N vice president had earlier urged PML-N supporters who had "bravely" cast their votes, especially in Daska, Wazirabad and Nowshera, amid violence, to now "guard their votes", as counting of ballot papers begins.
"I request the PML-N workers, especially from Daska, Wazirabad and Nowshera that the way they cast their votes with courage and determination amid thuggery by PTI government representatives and police, to display the same resolve and guard their votes," she wrote, in a message on Twitter, soon after polls closed at 5pm.
Her message came after a day of voting marred by violence, which saw the deaths of two and injury to at least eight people.
Clashes had broken out between PTI and PML-N workers in the Daska constituency, with each accusing the other of instigating violence to affect voter turn out.
By-polls, in total, were held today in four constituencies: NA-45 Kurram-I, NA-75 Sialkot-IV, PP-51 Gujranwala-I and PK-63 Nowshera-III.
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