Updated at 4.50pm with Delia reaction
A Nationalist Party insider and MP has hinted that the PN is in danger of being "overcome by Freemasonry".
Karol Aquilina prompted a storm of commentary and criticism on Facebook this morning after writing a cryptic post stating that "the worst thing that could happen to a Maltese political party is for it to be overcome by Freemasonry".
The post, which was accompanied by an image of the freemasons' square and compass symbols, prompted a barrage of criticism on Facebook, with many urging Dr Aquilina to be more specific.
When contacted, Dr Aquilina told Times of Malta that he was speaking in general terms, with no reference to any particular candidate.
"The Nationalist Party is opposed to Freemasonry - this is one of its principles and anyone who knows me knows how strongly I feel about the matter," he said.
"I have not endorsed anyone and I have not spoken about the candidates to anyone," he added.
He noted that PN MPs were all obliged to sign a declaration that they were not freemasons.
Dr Aquilina, a former Siġġiewi mayor who also chairs the PN's administrative council, was an ex officio member of an ethics committee which last week was tasked with looking into the suitability of leadership candidates.
The council Dr Aquilina chairs had unanimously urged Dr Delia to reconsider his position in the PN leadership race ahead of Saturday's first round election - a suggestion the Birkirkara lawyer ignored.
Dr Delia went on to win the first round election with 46 per cent of the vote and will now go head-to-head against Chris Said in two weeks' time.
Delia challenges Aquilina to substantiate claims
Dr Delia later challenged Dr Aquilina to substantiate his claims, adding that it was "ridiculous" for a party official to make a fool of those who had elected him by saying the party would be "snatched" by freemasons.
He appealed for rival candidate camps to stop attacking each other and other contestants, vowing that if he were elected, he would extend the hand of friendship to the supporters of the other candidates.