The Sunday Independent has dropped long-time columnist and former senator Eoghan Harris, over an anonymous Twitter account.
The paper says he was involved in the running of a fake account that mostly posted about Irish politics.
Editor Alan English says the material would never have been published in the Sunday Independent.
Mr Harris was a big critic of Sinn Féin - and the party's justice spokesman, Martin Kenny, says the paper was right to drop him.
Wicklow Hails Role Model Warren Kavanagh Who Calls Time On Successful Career
Wicklow Councillors Split On Local Property Tax Rates
Wicklow's Jack Reynor To Be Honoured In Los Angeles
Ominous Soundtrack Drowns Out Councillor's Message As Row Over Council Rent Hikes Rumbles On
East Coast FM's Jack Massey Among Ten Selected for the Learning Waves Journalism Graduate Programme