The emergency department at Roscommon County Hospital closed at 8am this morning and was replaced with a minor injuries unit for adults only.
150 people are protesting outside Roscommon Hospital this evening.
After consultation with local doctors, The out of hours GP clinic was moved from the County Hopsital to HSE offices on Lanesborough Road.
Earlier, 400 people gathered to protest the Roscommon closure outside the hospital. The protesters are marching around the hospital carrying flags, white crosses and signs.
Services for patients requiring urgent treatment are being transferred to hospitals elsewhere in Connacht.
The move has been criticised by GPs and community groups in Roscommon who claim there is widespread confusion about the new arrangements in place.
People in Co Roscommon requiring an ambulance will be brought to University College Hospital Galway, Sligo General Hospital or hospitals in Ballinasloe and Castlebar.
The HSE has advised those seeking urgent medical care not to attend Roscommon General Hospital.
The minor injuries unit will be supported by medical assessment facilities and a new out-of-hours GP service.
There will now be four ambulances based in the county, two in Roscommon town, as well as a 24-hour rapid response vehicle staffed by an advanced paramedic.
Earlier, the Health Service Executive had said that the emergency department at the Midland Regional Hospital in Mullingar was exceptionally busy and could not take any additional patients coming from the ambulance service.
Mullingar General Hospital has recommenced its ambulance service to the Accident and Emergency unit at the hospital.
Councillors resign party whip
Two Fine Gael councillors on Roscommon County Council have also announced that they have resigned the party whip in protest.
Dominic Connolly and Laurence Fallon say they made the move because the party failed to honour a pre-election commitment.
Speaking on RTÉ's Morning Ireland, Councillor Connolly said Taoiseach Enda Kenny and Minister for Health James Reilly should apologise to the people of Roscommon for failing to deliver on a written guarantee on hospital services.
Roscommon County Councillor Laurence Fallon has said that even though he resigned the Fine Gael party whip on the council this morning he has not resigned from the party.
Laurence Fallon has said he wishes to make the membership in Dublin and around the country fully aware of the deep dissatisfaction with the actions of the party's deputy leader Dr James Reilly.
It is understood councillor Dominic Connolly has also resigned the party's whip on the council but will not resign his membership from the party at this stage.
Both councillors have called on the Taoiseach to come to Roscommon to give an honest explanation about the future of the hospital.
Meanwhile, Sinn Féin President Gerry Adams, TD, has said that the closure of Roscommon Hospital's Emergency Department has put the Taoiseach's credibility on the line.
Mr Adams has said it is clear that Enda Kenny has broken a personal commitment he gave to retain services at Roscommon Hospital.
Gerry Adams has said that the Labour Party is also guilty of breaking election promises as its candidate in Roscommon gave a commitment on behalf of his party to retain services at Roscommon.
Elsewhere, the Fianna Fáil leader Micheál Martin has urged the Taoiseach to apologise to the people of Roscommon over misleading them in the lead up to the election.
50 protest at Mallow General Hospital
Around 50 people have taken part in a Sinn Féin protest against proposed changes at Mallow General Hospital.
They were joined by a number of patients at the hospital.
Mallow's emergency unit is due to close in November, to be replaced initially by a 12-hour urgent care unit and in April 2012 by a medical assessment unit.