FEARS are mounting for a whale, believed to be a rare humpback, which has appeared in the River Thames.
There were six sightings of the massive marine mammal - said to measure up to a staggering 33ft - in the river yesterday, the first at Tilbury in Essex.
The whale was seen spouting water in the River Thames near the Dartford Crossing today
And it was spotted again in the water near the Dartford Crossing between Kent and Essex.
If it is a humpback as believed, it would be the first time in ten years one of them has been spotted in the Thames.
The rare species can weigh up to 30 metric tonnes in adult form.
The whale has already been named online as “Hessy” - and was seen between Crayford Ness and the Queen Elizabeth II Bridge in Dartford, Kent - more than 60 miles in land from the sea - after midnight.
It comes just over a year since Benny the Beluga set up home further downstream at Gravesend last summer.
Twitter users have poured out sympathy for the animal with one imploring “hope it finds its way out again”.
Martin Garside, from the Port of London Authority, said the size of Hessy has ranged from between 16ft and 32ft.
He said: "There were a number of sightings by boats on the river during the course of yesterday.
"We have not had any confirmed sightings today.
"As far as the reports yesterday go, it is a dark-coloured whale with a small dorsal fin - so it is not anything like the beluga. This animal is darker.
"All we know at this stage is it is dark-coloured.
'NOT AN EVERYDAY SIGHT'
"There are varying estimates of size, between five metres and 10 metres.
"That is consistent in description with a humpback and also other types, including a minke whale.
"We are working with British Divers Marine Life Rescue, who are monitoring the behaviour of the whale and the type of species.
"It is not an everyday sight, although we have had a number of whales in the Thames."
Mr Garside added that it was "too soon to assess" how long the whale could be in the river for.
The British Divers Marine Life Rescue service confirmed the sighting of the whale.
A member of the team said: "We observed the humpback whale in the Thames Estuary for just over three hours today, the whale was diving and surfacing at approximately 5-6 minute intervals, slowly moving down river with the outgoing tide."
Stuart Cheyney, 43, of Erith, said: “It was feeding and spouting. You could see it with the naked eye, it was brilliant.”
Car worker Shaun O’Riordan, 52, saw the whale surfacing in Dagenham. He said: “I’d seen a few seals, even some dolphins but never a whale in the Thames.”
Tim Piles, 36, of Greenhithe, said: “I’ve been on a boat to see whales — you don’t expect it here.”
Experts said there was hope that it is healthy, as it is diving and surfacing in the normal way, every five minutes.
Julia Cable, from British Divers Marine Life Rescue, said: “We hope it will not be staying in the river for long although there is ample food.
“It’s come from the Channel or North Sea and could have had navigational problems.”
Fin here before
OTHER Thames visitors in the past 15 years have included:
2004: A short-snouted sea horse was spotted in the river and hailed as confirmation it was a clean waterway.
2006: A bottlenose whale, nicknamed Whaley caused hysteria in London when she swam upstream for three days. She sadly died from a heart attack after being rescued.
2009: A young humpback whale was washed ashore at Dartford. It was thought to have died of starvation.
2018: Beluga whale Benny spent three months in the river.
The whale has been nicknamed Hessy by some Twitter users.
One account, called Girl About the Thames, wrote today: "Hessy The Thames Humpback Whale was sighted at Ford Dagenham this morning.
Unfortunately it's headed further in."
Police Constable Dempster, a member of the Metropolitan Police Marine Policing Unit, spotted the sea creature during an overnight patrol.
He tweeted: "It was spectacular! Was gobsmacked it was so big. Would estimate about 15 meters."
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In September 2018 a beluga whale - normally found in the Arctic - was spotted in the River Thames near Gravesend, Kent.
It stayed in the river for around nine months before it eventually made its way out back out towards the North Sea.
Named Benny by animal lovers, it attracted large numbers of visitors who came down to the shore to catch a glimpse of it.
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