Amateur fossil hunters and beach goers on teh south coast are putting their lives at risk by ignoring warnings and closures at cliff edges.

Coastguards say large sections of England's fragile south coast is crumbling into the sea, with landslides caused when heavy rainfall mixes with soft stone and rock to create ''a potentially deadly porridge''.

Around a quarter-mile of Swanage Bay in Dorset, along the Jurassic Coast, has begun crashing into the sea this weekend, while Lyme Regis is among the areas also being carefully monitored by emergency services following days of torrential rain.

The potentially deadly combination of heavy rainfall and fragile rockface was brought into sharp focus this summer following the death of 22-year-old Charlotte Blackman from Heanor, Derbyshire, who was on holiday when part of the cliff at Burton Bradstock collapsed and crushed her.

Yet the following day, people were still sunbathing below overhanging cliffs within a short distance of where Miss Blackman died.

Despite the best efforts of coastguards and other emergency services, people are ignoring warnings about the perilous nature of the coastline.

Philip Chappell, a coastguard in Weymouth, said: ''Parts of the Jurassic Coast are notoriously fragile, particularly following this bad weather.

''The amount of rain we've had recently is turning parts of the cliff into a potentially dangerous porridge.

''The professional fossil hunters are no problem, they know the risks - but the amateurs don't really have a clue.''

In Swanage, local coastguards are keeping a watch on areas near the beach and beach huts as sections of cliff continue to move, and on Portland a section of coast path on the west of the island is particularly vulnerable.

Further west, sections of beach and cliff near Charmouth have suffered from cliff falls and mudslides.

Simon Dennis of Portland Coastguard said: ''With the poor weather continuing, we're dealing with a number of landslips and mudslides along the Devon and Dorset coastline.

''In Lyme Regis, coastguards and Dorset Police are dealing with an area to the west of the town, with very significant movement, including buildings overhanging the cliff edge.''

Earlier this week, an amber landslide warning was put in place by the British Geological Survey for the South West, who urged walkers to take care along coastal routes.