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A massive landfall has taken place in Dorset, changing the whole coastline in the area.

Over 4,000 tonnes of mud and rocks have fallen from cliffs on the Jurassic coast.

It's thought to be the biggest landslip to happen there in 60 years - with some boulders as big as cars.

It's a area away from houses and no-one has been injured - experts say it's a normal, if spectacular, sign of coastal erosion.

"It's completely natural and just shows the cliffs doing their thing" said Sam Scriven from the Jurassic Heritage Trust, "It's nature in action."

The cliff that has collapsed is around 450-feet high and Mr Scriven, a geologist explained what had happened.

"On the bottom of the cliff you have clay and above that is porous sandstone which has soaked up water from the rain over the winter months and got very heavy. The clay has got slippery and made it unstable and whatever the trigger was, it's just gone."

Visible in the rubble were trees and bushes from the top of the cliff and boulders from the cliff face - and some whole trees were seen floating out to sea.

The force of the collapse was so strong the beach has been blocked off and the sea is full of sediment from the landfall.

People are being told to keep away until experts can make sure the rest of the cliff face is safe.

Dorset Council said a "substantial" rockfall happened near Thorncombe Beacon with more movement expected as fresh cracks 1.4m deep had appeared near the cliff top fence line.

A further 300m of cliff east of Seatown also fell away leading to the coast path being cordoned off.

The Jurassic Coast is a World Heritage Site on the English Channel coast of southern England.

It stretches from Exmouth in East Devon to Studland Bay in Dorset, a distance of about 96 miles, and was put onto the World Heritage List in 2001.

The coastline covers 185 million years of geological history - covering the Triassic, Jurassic and Cretaceous periods.

At different times in the history of the earth, this area has been desert, shallow tropical sea and marsh - and the fossilised remains of the various creatures that lived here have been preserved in the rocks.