Sceilig Mhichíl (Skellig Michael) is closed to visitors following a rockfall.
It is understood that the rock became loose and fell from the cliff at around 4pm.
There were no visitors on the island at the time having left for the day, but Office of Public Works (OPW) staff, who reside on the island during the tourist season, were there.
It is understood they were brought to the mainland and that expert climbers will evaluate the potential damage tomorrow.
In a statement, the OPW said Sceilig Mhichíl has been closed to allow for a full examination of the site and to clear debris. It will reopen to visitors once it has been deemed safe to do so, it added.
The island opened on 15 May this year for visitors.
It lies 12km off the Kerry coast and is only accessible by boat, with vessels limited to 12 people each and making one trip per day only during the season.
The visitor season on the island normally finishes at the end of September and weather and sea conditions make it generally inaccessible after that.
The site has become a huge international attraction after it was used as a location for the Star Wars movies in recent years.
