ASTI general secretary Pat King has alleged that he experienced bullying and abuse on a website run and moderated by union members.

In a keynote address in which he pleaded for unity, and condemned the actions of dissenters who were trying to undermine the leadership, Mr King said the abuse levelled against him included a death threat and “despicable references to my children and grandchildren”.

He was commenting in the wake of what he called the "disgraceful" protests against Minister for Education Ruairi Quinn yesterday.

Mr King condemned the way in which the union’s president-elect was ignored when he made numerous attempts to “uphold dignity and respect”.

Mr King said “you either believe in free speech and respect and dignity or you don’t.”

He claimed there was a party political motivation behind both the heckling of Mr Quinn and the abuse he said he had received.

“Yesterday, in this room, I saw a man being abused, shouted down and treated disgracefully by a minority in this room.”

However, the main organisers of the protests denied knowledge of a death threat against Mr King and said any personalised attacks on their website had been removed in accordance with their moderation policy for the forum.

Mark Walshe, a teacher from Swords, north Dublin, who heads up the ASTI Fightback group, said there were a number of forums on which teachers commented including the ASTI's official Facebook page and the Fightback site.

As moderators of the latter, “we have a responsibility to make sure that there aren’t any negative comments or personal attacks” and so it removed a reference which Mr King complained about last January that had referred to his grandchildren.

“Now, the nature of that post basically said - and it wasn’t by us, it was by some other teacher who put it there - was how could he look at his grandchildren in the eye given that he has presided over all of the sell-outs in terms of the Croke Park I and Haddington Road when these sell outs would lead to the destruction of the education system.”

“That was the angle of the post. Now we committed to removing any post that was seen as in any way personally attacking because it would undermine the political message that we have.”

As for the other post referred to, Mr Walsh said “we have checked on our site and we can’t find any evidence of a death threat”.

Fellow protester Andrew Phelan, who used a megaphone to interrupt the Minister's speech on Tuesday, said Mr King was trying to use the allegation of bullying "to smear us".

Neither he nor anyone else in the Fightback group wrote the comments he referred to and it “could have been someone who wasn’t even a teacher”.

Mr Walshe said he along with other members of the left-wing group were “instrumental in starting” the disruption of Mr Quinn’s speech but he denied the protest was orchestrated.

“What King tried to say today is that it was only a small minority. There is no way it was a small minority. At least two thirds of people there at the meeting yesterday were totally opposed to what Quinn was doing.”

He said teachers had tried previously “to be reasonable with the Minister” but he had moved ahead with the Junior Cycle reform “unilaterally” and without listening to the profession.

Of his own politics, Mr Walshe said he was the only member of the Fightback group who was a member of a political party - People Before Profit - while Mr Phelan had been a member of the Socialist Party.

"So yes there is a political element to it; we don't deny it… But there are people the union in Fianna Fail, Fine Gael and Labour.

People in political parties care about issues that affect society overall, whether it’s education or health. So it’s not unusual. Nobody in the ASTI can criticise people for being in political parties.”