With counting of votes still underway, the PTI is currently in the lead, followed by the PML-N and the PPP, based on results from 26 percent of polling stations nationwide.
The poll results have been roundly criticised. PML-N president Shahbaz Sharif has said his party rejects the poll results "due to manifest and massive irregularities".
PPP Chairman Bilawal Bhutto Zardari also voiced alarm, saying he has not received official results from any constituency he is contesting and that his party's polling agents have been thrown out of polling stations across the country.
In response, the ECP has denied the allegations and asked all parties to raise specific complaints of irregularities with the commission.
We talked to our analysts to get their take.
Zahid Hussain, analyst
The political parties are complaining about the delays in the counting and the rigging allegations. What does this suggest in your view? Is this really happening?
After every election, we usually hear this kind of complaint, so this is nothing new. So each time the party which loses the election always has this kind of complaint.
Don’t forget, in 2013, [there were allegations of] election rigging. So this is kind of usual.
But nevertheless, I think, their complaints should be addressed; the ECP should respond to these complaints, there should be some investigation so that the elections should be more transparent.
But what I am trying to say is that, unfortunately in Pakistan, there is no tradition of accepting election defeat more gracefully. There is no example of that.
In 2013, the PTI also claimed that the elections were stolen. They went on dharnas to demand the opening polls of four constituencies.
Does delaying results constitute a rigging practice in itself?
Not at all. Even the last election, it's exactly same case. It's always like this. Sometimes the results are coming out, sometimes there is some kind of delay, and I don’t see any abnormality in that.
It's not unusual. It's a common practice. But still it should be investigated.
Arifa Noor, analyst
So the PML-N has rejected the result completely. What does that suggest about what's happening?
We will have to see what they mean by rejection. Rejection in itself is a very vague term.
Are they saying they are not going to go to the parliament? They are not going to occupy the seats?
Now, if they take such a drastic step, that basically means they will lose some of their people who have won on these seats.
Because chances are, again this is all hypothetical, I can’t say anything for sure, but the thing is that when you have so many candidates who have won, they have probably spent a lot of money to win this election.
And some of them will want to make it to the parliament, take oath and sit there.
So if the PML-N takes such a drastic step, there are chances that there will be defections from the party. Because not everyone will want to make this sacrifice.
And if I can think of this, the chances are that the PML-N leadership is also aware of this. This is like the nuclear option.
And they are willing to risk that?
There is a good chance that they will not take this drastic step. They will clearly need to define or figure out a strategy of how they will go about this. Till we know what their strategy is, it is hard to comment further on this.
Before this, parties were complaining about delays, about polling agents being kicked out of the stations. Can you tell us what could have been happening inside the polling station during this time?
I have no idea, very honestly. Because at the moment they are making these allegations but we really don’t know.
They will have to figure out how they are going to proceed with these allegations. Generally what tends to happens is that, if something like this happens, the ECP sets up an election tribunal and most people who have complaints take their complaints to the tribunal.
There is a legal process that can go on for years. When Jahangir Tareen and Usman Dar went to the election tribunal, it took more than an year for this to be sorted out.
Also, there is no way to prove these allegations legally. The legal process is the election tribunal and then of course the superior judiciary with the right of appeal.
The second option is that they should do some kind of a public protest, the way Imran Khan did with the dharnas.
So we have to see how the PML-N builds on their initial response.
Also, keep in mind the fact that going into the election tribunal is a very, very expensive process. A lot of people may kick up a fuss about rigging and being treated unfairly, but they may not take that to the tribunal because, you know, that can be an expensive process.
Last time too, the three or four PTI candidates who did this were the very wealthy.
Adnan Rasool, analyst
It started with complaints during the day of slow polling and then it morphed in to accusations out of outright rigging.
So far, the Pakistan Muslim League-Nawaz (PML-N) has rejected the results of the elections outright, while other parties, including the Pakistan Peoples Party (PPP) and the Pak Sarzameen Pary (PSP), have raised serious concerns about the legitimacy of these elections.
But instead of getting tied up in political rhetoric coming from all sides, it is pertinent to understand what is going on exactly and how are these alleged irregularities being carried out.
Slow polling is a tactic used often as part of any rigging scheme. Most of the rigging in elections technically happens before the elections are conducted. Election day rigging is historically much harder to pull off without invoking suspicion.
Slow polling is an election day rigging tactic. It is a technical way of voter suppression. Most people tend to vote in the afternoon or evening as it is a public holiday and people are slow to come out.
At that point, the polling stations are choked with people, leading to long lines. The slower processing then leads to not all people getting to vote or being turned away due to the long wait.
The logic here is simple: in areas where a specific party has a heavy voter base, by slowing down the polling process their voters are turned away.
The tactic is completely legal and is combined with the often-used strategy of delaying the opening of the ballot boxes by up to 15 minutes after polls close. This is how election day rigging has historically taken place in Pakistan.
In 2002, as well as in earlier elections where the powers-that-be wished to promote the party of choice, this strategy was adopted as it cannot be challenged for being illegal.
Other strategies that are often used include missing election day supplies that delay the starting of the polls or cause the polling stations to shut down for a few minutes until they restock supplies.
In these elections, evidence suggests the go-slow is in full force.
What parties are accusing is happening right now is that, even though it is past midnight, the results from most polling stations are missing.
The accusations include candidates' polling agents being kicked out while the votes are counted, as well as results not being certified by the returning officer.
Either way, what is allegedly happening now is that results are being altered to suit a specific political party at the expense of others.
The way it is being allegedly done is a manner which has not been witnessed since 1977. Questions are being raised about why only 26 per cent of polling stations have been accounted for when last time around, by this time, most of the results were out.
Even in cities like Lahore or Rawalpindi, most of the results are being allegedly withheld. And that is prompting the accusations of widespread rigging.
The problem with this scale of accusation is that it questions the legitimacy of the new government and their authority from day one.
No matter what the next government says or does, the kind of scenes being allegedly witnessed right now will be hard to move past when a significant part of the population simply does not acknowledge the results of these elections any more.
Rigging has been alleged in many elections but, this time, the sheer scale of it is what casts a shadow on these elections.