Authorities have urged the public to stay away from a landslip on the beach at Nefyn.
North Wales Police said emergency services had been alerted to the scene near the beach car park on Tuesday afternoon.
A spokesperson said: "We are advising anyone in the immediate vicinity to stay well away from the affected area both above and on the beach, as more landslides may occur."
They added police, coastguards and Cyngor Gwynedd are assessing the situation "as a matter of urgency".
There are no further details at the moment.
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