The search for a whale reported in shallow water off the coast of Mundesley in Norfolk this morning has been stood down as there have been no further sightings.
The Maritime and Coastguard Agency confirmed the operation was being stood down as there had been no sightings of the whale for 90 minutes.
A member of the Mundesley Coastguard rescue team contacted the UK Coastguard just after 10am to report the whale was 300-400 yards offshore.
The whale was reported to be alive and thrashing about in the shallow water.
UK Coastguard alerted Happisburgh and Mundesley Coastguard rescue teams. British Divers Marine Life Rescue, the Zoological Society of London, the Maritime and Coastguard Agency's Receiver of Wreck and the local council were also informed.
Keith Griffin, station officer for the Happisburgh and Mundesley Coastguard Team, said: 'We've carried out an extensive search and are confident that if the whale was in that search area, we'd have found it.
'Low tide has now passed so with a bit of luck it will return to deeper waters and stand a chance of survival.'
The next low tide, when the whale is most likely to become stranded, is expected at about 2am on Wednesday.
Earlier, UK Coastguard Mike Puplett said: 'We are advising people to keep at a safe distance from the whale, so we do not cause any further distress to it. We are doing all we can to assist the local authorities and allow those with rescue experience to do their work.'
A spokesman for North Norfolk District Council said: 'We are in liaison with the Maritime and Coastguard Agency about a reported whale offshore at Mundesley and are ready to respond if and when the situation requires it.'
If the animal does die on a north Norfolk beach, the council would be responsible for its disposal.
There have been no reported sightings of the whale since it was first spotted this morning.
But the coastguard has appealed to the public to keep their eyes peeled.
Keith Griffin, station officer for Happisburgh and Mundesley coastguard team, said: 'We've carried out an area search from Overstrand right through to Sea Palling and not spotted anything at all.
'We were called at 10.15am by Humber coastguard. They had a report of a whale 400 metres from Mundesley beach.
'We don't know what sort of whale it is but we are asking if any member of the public spot it to dial 999 and ask for the Coastguard.'
The latest sighting follows the death of two sperm whales at Hunstanton earlier this year - the first in January, the second in February.
In total, 29 whales have died in the North Sea this winter, six of them off the east coast.
Dr Peter Evans, director of the Sea Watch Foundation, believes the whales have landed in trouble in the shallow waters after travelling south in search of squid.
He revealed he will be 'surprised' if the latest sighted whale doesn't get stranded, having been spotted so close to shore – and warned more could follow.
Dr Evans said: 'I fear it is very likely that it will strand, because they almost invariably do; I will be surprised if it doesn't. 'I think the fact that we are getting more strandings means there are more animals out there - the pod was really quite big and dispersed, we simply that we haven't accounted for all of them yet.
'As soon as they get beyond the central North Sea they are likely to get into difficulties because it is much shallower there. It's very hard for them to navigate out of those areas, their sonars won't function so well because it's so shallow.
'We've had incidents like this before but this is the biggest number we've ever recorded in the North Sea.'
It is unclear whether the whale spotted near Mundesley was part of the same pod of whales stranded at Hunstanton.
However, rescuers have warned if it does become stranded there is little they can do to help.
Hunstanton Sea Life Sanctuary manager Nigel Croasdale, who has been involved with two unsuccessful rescue attempts in recent weeks, said: 'Once they come into shallow water and start getting beached it is an almost impossible task to rescue them due to their size.
'They are so large if you attempt to drag them back into the sea you inflict more damage. And, even if you had the equipment, the likelihood is it would become beached again the next day.
'The outcome as to whether an individual whale is going to make it is really in the hands of nature.
'If they do come ashore, all we can do is make them as comfortable as we can. The best thing for their last few hours is to relieve them of as much stress as we can do, and we can do that by controlling crowds of people and reducing the noise.
'It's like standing next to a loved one's bedside when the prognosis is not good.'
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