Irish Agriculture Minister Dara Calleary and Senator Jerry Buttimer have both resigned after attending a golf society event indoors with 81 other people.
They were guests at the Oireachtas Golf Society event, which also included Independent TD Noel Grealish as well as EU Commissioner Phil Hogan and former attorney general Seamus Woulfe.
The event was held at the Station House Hotel in Clifden, Co Galway.
Current guidelines state that no more than 50 people should gather indoors.
It came as gardai confirmed they have launched an investigation into the event.
A statement said: “An Garda Siochana is investigating an event that was held in Co Galway on the 19th August 2020 into alleged breaches of the Health Act.”
Gardai said that, as it is an active investigation, they have no further comment to make.
People all over the country have made very difficult, personal sacrifices in their family lives and in their businesses to comply with Covid regulations.
“This event should not have gone ahead in the manner it did
Taoiseach Micheal Martin said in a statement: “This morning Deputy Dara Calleary tendered his resignation as Minister for Agriculture, Food and the Marine, following his attendance at the Oireachtas golf dinner on Wednesday evening.
“His attendance at this event was wrong and an error of judgment on his part. I have accepted his resignation.
“People all over the country have made very difficult, personal sacrifices in their family lives and in their businesses to comply with Covid regulations.
“This event should not have gone ahead in the manner it did given the Government decision of last Tuesday.
“Dara Calleary, since he was first elected to Dail Eireann, has been, and remains, a committed and dedicated public representative.
“This error of judgment was out of character. He has made the right decision for the country, particularly in the light of our continued efforts to suppress Covid-19.”
Mr Calleary cancelled a number of media appearances he was due to make on Friday morning before his resignation was confirmed.
He quits the Cabinet just five weeks after being appointed to the role following the sacking of Barry Cowen.
Mr Cowen was dismissed after he refused to provide further public statements on his 2016 drink-driving offence.
Mr Grealish also apologised “unreservedly” after attending the hotel dinner.
Mr Grealish, who is the captain of the Oireachtas Golf Society, told Galway Bay FM that he sat at a table with six people and practised social distancing.
He claimed he had been assured that the event met new public health guidelines, but now realises his error of judgment.
Fianna Fail Senator Aidan Davitt also issued an apology over his attendance.
In a statement posted on Twitter, he said: “I apologise unreservedly for attending a function in Clifden following a golf event in Connemara last Wednesday.
“In light of the updated public health advice issued on Tuesday, I should not have attended this dinner.
“I genuinely apologise unreservedly for this error of judgment.”
Education Minister Norma Foley said Mr Calleary’s decision to attend the event was a “very serious error of judgment”.
“I understand the anger and frustration and indeed the disappointment,” she added.
“We are all being asked to play our part as we journey through Covid-19 so it absolutely should not have happened.
“But equally so, I want to say that Dara has made a fulsome apology, his remorse is absolutely genuine, and he has put up both hands now and he has resigned, and I think that is a measure of the man that he has done that.”
Mr Calleary apologised in a statement issued on Thursday night.
He said: “Last night I attended a function I committed to a number of weeks ago, to pay tribute to a person I respected and admired greatly.
“In light of the updated public health guidance this week I should not have attended the event. I wish to apologise unreservedly to everyone.
“We are asking quite a lot from everyone at this difficult time.
“I also offer this apology and my sincere regret to my Government colleagues.”