Three candidates from the Pheu Thai and Future Forward parties yesterday called on the Election Commission (EC) to hold runoff elections in Bangkok's Bang Kapi and Phaya Thai districts.
They are Nitcha Bunlue, of the FFP and Trirat Sirichantharophat from Pheu Thai, both running in Constituency 13 in Bang Kapi district of the capital.
And in Phaya Thai district, there is Chris Potranandana, an FFP candidate running in Constituency 6.
Mr Trirat said there were many irregularities at polling stations in Constituency 13. The most serious accusation being that some votes in the constituency had been bought at 500 baht a head. He also complained that the number of voters was less than the number of ballots counted and that the vote counting and announcements were conducted under unusually dim lights.
Nitcha Bunlue, an FFP candidate questioned why the number of votes for her "suddenly dropped" by more than 400 during counting after she had earlier been ahead of her election rivals.
Mr Chris said conditions in his constituency's polling station had also been unacceptable.
"The polling station did not afford voters any privacy. People in the station could see who was being voted for," he said.
The three candidates who appeared at the EC office yesterday all missed out on Lower House seats in Sunday's election but believe it was cheating that led to their defeats. They are the latest group to make official complaints to the EC, which is now struggling to deal with mounting public criticism of its "confusing election results".
On Wednesday, veteran Democrat politician Nipit Intarasombat, who lost in the party's southern stronghold of Phatthalung, demanded the election watchdog look into alleged vote-buying.
His evidence included screenshots from the Line chat application and video clips which he said proved vote-buying had occurred in Constituency 2.
One candidate allegedly spent more than 30 million baht to secure a seat in the Lower House, he said.
"What I want to find out is whether the EC can do its duty, especially regarding claims that a party executive was involved in the wrongdoing," he said.
In another development, former army officer, Capt Songklot "Capt Pu Khem [salted crab]" Chuenchuphon, petitioned the EC to dissolve the FFP and Pheu Chart parties.
FFP leader Thanathorn Juangroongruangkit's comments on the prosecution of ousted prime minister Thaksin Shinawatra could be construed as being in contempt of court, Capt Songklot claimed.
He also accused core red-shirt member Jatuporn Prompan of influencing the Pheu Chart Party, in violation of the organic law on political parties.