A Sinn Féin member in Wexford has resigned from the party after using false social media profiles to abuse businessmen, politicians and celebrities.
Fianna Fáil senator Malcolm Byrne said he was on the receiving end of derogatory online messages from an account created by Paul Heffernan.
Wexford businessman Derek Webb was also subjected to derogatory comments from an anonymous Twitter profile, which used the name "P O'Neill", a code-name often used by the Provisional IRA to sign statements.
The same profile also sent abusive messages to model Claudine Keane about her husband Robbie Keane.
In one message, the anonymous account wrote to Mr Webb and asked "are you that fat pig that cycles around Gorey in the Lycra with your man tits hanging out."
Other tweets called him a “fat sloth lookalike clown.”
In another tweet, he was asked “did special school bring you up to Dublin for the day.”
Mr Webb investigated the anonymous account and eventually confronted Mr Heffernan, before complaining to Sinn Féin.
Mr Webb said he examined the tweets on the @peeoneill account on Twitter and cross referenced them with posts on Mr Heffernan’s other account, which was registered in his real name. He found both accounts tended to tweet about the same things on the same days.
“I went to the guards and they told me it could take a year to get the IP address from Twitter so I decided to confront him myself,” Mr Webb said.
He said he arranged to meet Mr Heffernan and confronted him with the evidence, leading to Mr Heffernan admitting to being behind the account.
“My tweets were at the lower end. They were water off a duck’s back. But the stuff against Malcolm Byrne was different,” he said.
In a letter to Mr Webb, the party said the messages were “not orchestrated or encouraged” by Sinn Féin.
“Our county board have recently been made aware of an allegation regarding a false social media profile operated by a party member that we understand has caused you distress to date.
“On behalf of County Wexford Sinn Féin, I would like to take this opportunity to express our condemnation of this type of behaviour and to reassure you that the actions of the individual involved were of their own doing and were no way encouraged or orchestrated by our party.
“By extension we also wish to express our regret of this individual’s actions and would like to extend our apologies to you for any distress caused.
“Sinn Féin at both local and national level is actively opposed to cyber bullying or any form of discriminatory behaviour. As you may be aware the individual in question has now offered their resignation to the party which I can confirm has been unanimously accepted by our elected county board.”
The letter was signed by Roger Kiernan, the chairman of the Wexford Sinn Féin branch. It is understood the letter was sent last Friday.
Mr Byrne said that Mr Heffernan admitted to using social media, particularly an anonymous Twitter account, “to direct abuse at politicians in parties other than Sinn Féin and others.
“I was one of those whom he attacked. The abuse went well beyond criticism of policy and was personalised and in many cases, nasty. I blocked the fake account and reported it to Twitter but the company did not take action.
“It was only the work of a local businessman and community activist, Derek Webb, who also suffered abuse from the troll, who uncovered the person responsible. Derek confronted Paul Heffernan about his online activities. He also raised it with Sinn Féin.
“I would welcome the statement by Sinn Féin in disowning the online abuse by one of its now former key activists in Wexford. The party has rightly made clear that this anonymous trolling is not acceptable.”
Mr Heffernan said he had no comment when contacted on Monday. The @peeoneill account is no longer active on Twitter.
