Two thousand people are taking part in a march in Dublin today calling for the release of anti bin tax campaigners from Moutjoy Prison.
A "letter of solidarity" will be handed in to Mountjoy at the end of the march which commenced at noon and will proceed to Mountjoy.
The letter from the Dublin Council of Trade Unions, which has organised the march, is sharply critical of the stance taken by local authorities in the current controversy.
Ten protesters were jailed by the High Court this week when they refused to give undertakings not to interfere with Dublin City Council's bin collection services.
Socialist Party politicians Mr Joe Higgins TD and Cllr Clare Daly are also serving sentences for defying a High Court order banning them from obstructing the waste collection service of Fingal County Council.