Papua New Guinea's Electoral Commissioner has ordered that six ballot boxes from a polling area in Jiwaka province be set aside.
A group of 28 candidates in Jiwaka's North Waghi electorate this week filed a petition with the Provincial Election Steering Committee disputing the fairness of polling at a polling place.
Video footage has surfaced from this electorate which appears to show rampant mishandling of ballot papers at a polling place by polling officials and other men.
The Commissioner Patilias Gamato said the manner in which the marking of ballot papers at the Singirok Barracks earlier this month was not lawful.
He said he has ordered the electorate's returning officer, through the election manager, to set the six boxes in question aside as disputed boxes.
Mr Gamato said he will direct a "thorough investigation into this incident to find out who was involved in making that decision to hijack the electoral process".
Meanwhile, as vote counting for the national election continues, a third result has been declared in the Rabaul Open seat where the sitting MP Alan Marat has been re-elected.
A number of sitting MPs are struggling to hold on to their seat, including the incumbent opposition leader Don Polye in Kandep.
Mr Polye is still trailing Alfred Manase of the ruling People's National Congress.