The man who interupted the transmission of last night's edition of The Late Late Show on RTÉ Television was released without charge at around midnight.
The programmed was disrupted for a time after the incident in which the man shouted abusive comments at presenter, Pat Kenny, and Gay Byrne before being removed by security staff.
The man was arrested by gardaí and taken into custody.
The programme resumed after a short time.
Mr Kenny today declined to comment on the incident.
One of the three guests on the set, Linda Martin, said she feared the protester had a knife or a gun as he shouted obscenities just feet from her.
The You're a Show judge said: 'I really don't know what was in his mind.
'I kept watching his hands and I thought to myself this fella is going to produce a gun or a knife at some point. That's what was in my mind.'
She added: 'I'd say there were quite a few in the audience who were thinking the same thing - this fella is just going to flip the bean altogether.'
She said Mr Kenny stayed very calm and everybody took their cue from him.
'Initially I wasn't frightened because Pat stayed very calm. He stayed very focused. The audience didn't flinch and we didn't move.'
Ms Martin said the man had emerged from the right-hand side of the audience. 'I think he must have sneaked in at some point and hid himself around the corner because he caught my eye as he walked over to where Pat was sitting.'