Several thousand protesters jeered the Taoiseach in Waterford yesterday in their campaign for a radiotherapy unit for cancer patients in the south-east.
Mr Ahern's car was showered with daffodils and held up for several minutes when it became surrounded by a group which jeered and heckled him.
He later jokingly thanked taxpayers for providing him with a sturdy Mercedes, which was not easy to overturn.
The Mayor of Waterford, Mr Hilary Quinlan, said the protest was supposed to be "silent and dignified" and apologised to the Taoiseach that a small minority of people had not adhered to that.
The lack of a radiotherapy unit in the region was an "emotive issue", he told Mr Ahern at a function at Waterford Institute of Technology, where the Taoiseach opened a new library.
A 50,000-signature petition calling for a radiotherapy unit was later presented to Mr Ahern by the South East Cancer Foundation, which organised the Daffodil Day protest.
Cancer patients in the south-east must travel to Dublin or Cork for radiotherapy. Most are treated at St Luke's Hospital in Dublin, where there is an eight-week waiting list. When admitted, they face round-trip journeys of up to 200 miles a day for treatment.
Mr Ahern told reporters the issue was raised by every delegation he met from Waterford. "I'm very conscious of the strain of people travelling when they're at their weakest. I understand all of that," he said.
He denied suggestions that an expert group examining the issue, which is due to report to the Government shortly, had already decided against recommending a radiotherapy unit for the region.
"That is totally untrue. There is no such decision made," he said.
Workers at Waterford Crystal left the factory for an hour to join the protest, which took place outside the institute entrance.
There was laughter at the library opening later when Mr Quinlan said he hoped Mr Ahern would experience "the hospitality and friendship for which Waterford is renowned". Mr Ahern said he was glad he was "still a good crowd-puller".
As for those who had surrounded his car, he said: "I know most of them personally. They travelled from my own constituency."
