"They came, they saw, they conquered, " was the verdict of Shell's Irish spokeswoman, Karen Cahill.

"Then they got bored and went home, " she told the Sunday Tribune.

Close to a dozen people from both the Workers Solidarity Movement and leftwing republican group, Eirigi, entered the building shortly after 10am on Tuesday.

The group were demonstrating against what they perceived to be the "theft" of Ireland's natural resources regarding Shell's Corrib gas field.

The protestors locked themselves into the lobby of Shell's Corrib House on Dublin's Leeson street and hoisted a banner above the door reading "Stop the Gas Giveaway".

A statement from Eirigi's website slammed Shell's arrogance for calling their headquarters, "Corrib House" the same name as the controversial gas field.

"Shell, in true arrogant style, have chosen to name their headquarters in Ireland, 'Corrib House', " according to a statement by Eirigi spokesperson, Brian Leeson.

"This is despite the fact the Shell's only role in Corrib, is to steal the area's natural resources, impose an unwanted refinery on the community, and to conduct a smear campaign against any group or individual who protests against this activity, " the statement continued.

Gardai arrived on the scene shortly after and the protest was finished by lunch-time.

It is all part of life at the headquarters of the controversial petroleum company according to Ms Cahill. She believes that the protest was sparked by third-level colleges being on holiday.

"I think the colleges are off at the moment. We usually get a bit of activity around then. It's just part of life here.

They seem to do this every so often, " she said.

"They didn't ask to speak to anyone from the company, they just waited in the lobby.

It was all very peaceful, " she concluded.