Thailand's state Election Commission has agreed to investigate whether the leader of a popular new political party that ran a strong third in last month's general election may not have been qualified to run as a candidate.

Thanathorn Juangroongruangkit, leader of the progressive Future Forward Party, already faces several criminal complaints and protests to election authorities that could lead to his or his party's disqualification.

The commission said Tuesday it found evidence that Thanathorn is a shareholder in a mass media company, which would disqualify him from serving in Parliament.

Thanathorn's supporters believe Thailand's conservative establishment is trying to eliminate his party to boost the chances of their favored candidate, Prayuth Chan-ocha, who has served as prime minister since leading a 2014 military coup.