A large section of Dover's famous white cliffs has broken away and crashed into the Channel, according to the coastguard.
Tonnes of rock collapsed into the sea between Langdon Cliffs and South Foreland Lighthouse.
Dover Coastguard said no-one was injured during the "substantial" rockfall, which happened in an area know locally as Crab Bay.
The National Trust has put up warning signs to alert walkers.
A full survey is expected to be carried out to determine the amount and length of cliff that collapsed on Friday.
A spokesman for Dover Coastguard said: "We can see the start of it from where we are based but then it goes round the corner.
"It appears that it crumbled from the top at high water so there was no-one down below at the time. It was quite a substantial fall.
"No-one was injured but it does serve as a reminder that if people are walking along the cliff-top or underneath, that the cliff can crumble away.
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