PEOPLE are being urged to heed warning signs and stay away from cliffs after a massive landslip when 400 tonnes of rock crashed onto a West Dorset beach.

Rescuers are confident no-one is missing after the landslip at East Beach, West Bay on Saturday.

The beach has been closed off with the cliff around the fall area described as 'very unstable.' Local authorities and landowners will be meeting to determine the best course of action but in the meantime the public are advised to keep well clear of the cliff top and bottom until further notice.

A major search and rescue operation was launched as about 20 people were walking on the beach at the time - but it was unclear if anyone was in the fall area.

Police, firefighters, coastguards and paramedics were sent to the scene about 2pm.

See a video of the operation here

The scene is about a mile from Freshwater Beach where holidaymaker Charlotte Blackman, 22, was killed in a landslide in the summer of 2012.

Authorities have been warning recently about unstable cliffs after heavy rainfall.

Rescuers used thermal imaging equipment before specially-trained sniffer dogs were brought in.

The rock came crashing down from the iconic East Cliff, the inspiration for the ITV hit drama Broadchurch which was filmed in the area.

Speaking at the scene on Saturday, incident commander Angus Nairn of Dorset Fire and Rescue Service said: "There was a severe rockfall at West Bay and it was unconfirmed whether anyone was missing.

"As a precuation, a multi-agency operation led by Dorset Fire and Rescue Service was launched to confirm the facts.

"From the intelligence we have received there are no persons believed to be missing that we are aware of."

He said the incident was being stood down after a sniffer dog was brought in to check the landslip area.

Mr Nairn said it is estimated that about 400 tonnes of rock fell onto the beach.

The Portland Coastguard helicopter flew over the area to identify any further weak spots. The area of cliff around the slip was identified as 'very unstable.'

The beach has been closed between West Bay and Freshwater for the 'foreseeable future,' Mr Nairn added.

Lisa and Andy Holloway, on a day trip from Yeovil, were standing on the pier when they witnessed the fall.

Mrs Holloway said: "We were so worried because there were at least 20 people walking on the beach at the time it happened.

"Some were the other side of the fall and some were this side (West Bay) but we didn't know if anyone was trapped under it.

"Some people immediately tried to climb on top of the fall but then there was a cloud of dust and we couldn't see anymore."

The landslip at West Bay has highlighted how the risk of landslides and rock falls has increased following severe weather and extreme sea conditions across the county's shoreline.

People are being advised not to walk or climb over debris and not take any unnecessary risks, and stay away from cliff tops and the base of cliffs as more landslides and rock falls could happen at any time.

Tides have also re-shaped and stripped beaches around the coast meaning it is easier to get cut off by the incoming tide.

People are advised to keep to official routes and follow warning signs at all times as the coast path will be very muddy and slippery in places.

Dorset County Council's emergency planning officer Simon Parker, said: “I would urge anyone visiting the coastline around Dorset to obey warning signs, stay on public footpaths and keep out of restricted areas or paths which are closed.

“The coast is actively eroding and of course that’s why it is so important from a scientific viewpoint and also attractive to visit.

“But that also means landslides and rock falls do happen, and although these are difficult to predict with certainty, factors like heavy rainfall can increase the risk of this happening.”