The Ireland-Israel Alliance has described as shocking an incident in which a businessman who was visiting Dublin from Tel Aviv said he was spat at while dining with a colleague and verbally abused by a group.
They say it was shocking incident of pure hatred and said they expected gardaí to follow it up.
Tamir Ohayon, 26, from Tel Aviv, Israel, was visiting Dublin for a business conference.
He said that nobody intervened during the "attack" and that they "chose not to care".
"People just kept eating," he said.
"I felt helpless and disappointed. I saw faces of people watching me be assaulted."
Mr Ohayon said that he did not feel safe in Dublin after the incident and "locked" himself in his hotel room.
He is now in Berlin and said he "didn't realise how scared I was".
"I didn't sleep the whole night. I don't think I'll ever step back in Ireland," the young man added.
Gardaí say they are investigating a public order incident at a Dublin bar that happened at around 9.30pm on Wednesday.
An Garda Síochána said in a statement that no injuries were reported.
Footage of the incident is circulating online.
Cathaoirleach of Dún Laoghaire-Rathdown County Council, Jim O'Leary, condemned the incident as "pure, unadulterated anti-Semitism".
"When people can spit at visitors in a bar and nothing happens, that's where we are at."
He said that Jewish people in Dublin feel "under pressure" and "marginalised".
"I would hope that this is an isolated issue," Mr O'Leary added.
