Tanaiste Joan Burton has attacked a politician who took part in an anti-water charge protest on Saturday which ended in her being barricaded in a car for two-and-a-half hours.
The Labour leader and Social Protection Minister claimed protesters rocked a car she was in, banged on its roof and attempted to overturn it.
She also reported missiles including eggs and full plastic water bottles being hurled during the increasingly heated confrontation.
Ms Burton had to be escorted from An Cosan College, Jobstown, Tallaght, where she had been attending a graduation for adults who went back to education, after the Garda riot squad was called in.
The minister rounded on Paul Murphy, Socialist Party and Anti-Austerity Alliance TD, who she accused of smirking while she was barricaded into a car and later bundled from one Garda car to another to escape the crowds.
Ms Burton described the protest as anti-democratic and led by ultra factions.
"They were rocking the car, banging on the windows, on the doors, on the roof, basically I suppose trying to turn it over," she said.
"Paul Murphy as a TD, he was standing at the back with a loud hailer leading the chanting - if that's his idea of a peaceful protest I would not like that norm being set by him as the way people in Ireland protest."
Ms Burton added: "Normally people who arrange protests, they are somewhat responsible for how they are conducted. For a public representative, smirking about that kind of action against our gardai perhaps he needs a rethink on it."
The protest became intimidating when Ms Burton attempted to join the academic procession with celebrating graduates from An Cosan and also when she got into her ministerial car and attempted to leave.
Videos posted online showed she was surrounded by dozens of chanting protesters who used placards to bang on the vehicle.
Other clips showed the number of protesters swelled quickly with ultimately hundreds of people surrounding and crowding the car and the streets around An Cosan which prevented her from leaving.
Ms Burton was eventually moved into a Garda car and then transferred a second time to evade the protesters.
Mr Murphy denied protesters tried to overturn the ministerial car and said a small number of young men who were initially not involved in the anti-water charge protest were responsible for eggs being thrown.
He said photos which showed a man throwing a brick at the back of a Garda car were taken after the protest had finished and the Tanaiste had left the area.
"All protesters behaved in a peaceful manner," he said.
Mr Murphy, who represents the area in the Dail, said the demonstration had been organised by local people the evening before.
He said he took part in a sit-down protest to prevent the Tanaiste leaving for half an hour and later he remonstrated with the crowds to allow Ms Burton to be driven out at a slow pace on the basis that the riot squad withdrew from the area.
"We did not lose control of the demonstration," he said.
Mr Murphy vowed to continue supporting and organising protests until the planned fees for water are dropped.
The Government is expected to unveil a revised charging regime this week with incentives including a 100 euro welfare payment for households which register and grants for conservation schemes.
Senator Katherine Zappone, co-founder of An Cosan, said the protest was menacing and accused some of spitting.
"As someone who witnessed much of what unfolded I have no hesitation in saying that what occurred went beyond legitimate peaceful protest," she said.
Fellow co-founder Ann Louise Gilligan added: "Those behind today's actions could easily have made their views known without resorting to tactics which do not enjoy public support."
Meanwhile, Health Minister Leo Varadkar called on constituency colleagues and Socialist Party TDs Joe Higgins and Ruth Coppinger to publicly dissociate themselves from the intimidation at the protest.
"The protest in Jobstown saw behaviour of the worst kind. There are reports of intimidation, aggression, sexist remarks and abuse of the gardai who were trying to keep the peace. Essentially, a happy graduation day was hijacked," he said.
"Protest is a right in any democracy. Protest has achieved many positive changes. Intimidation achieves nothing but a culture of fear. There is no place for this sort of behaviour in a modern democracy."