IFP leader Mangosuthu Buthelezi has reportedly lodged a complaint to the IEC about allegations of "vote manipulation".
According to SABC News, Buthelezi claims his party has received information about "irregular incidents" at some voting stations, but would not mention the exact areas.
He reportedly made the claims in Ulundi in northern KwaZulu-Natal after casting his vote on Wednesday.
The IFP leader reportedly said he was confident about the IFP's prospects of growth but raised concerns about vote manipulation.
On Wednesday, Buthelezi indicated that he would not be retiring from politics as reported earlier.
Buthelezi announced his retirement as president of the IFP in late October 2017. He said he would not stand again for leadership of the organisation he founded in the mid-1970s, News24 reported.
But when asked during a media briefing about his political future plans after the elections, Buthelezi said: "Of course I am going to Parliament", IOL reported.
He reportedly told his supporters that his party might collapse if he abandoned it.
"As long as I am still alive I will not leave my party; I will assist the leadership that will be elected," he reportedly said.
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