Rescuers are trying to save a whale stuck on the River Thames in west London.
The whale, thought to be a young minke whale, was first spotted at Richmond Lock and Weir at around 7pm on Sunday.
A Royal National Lifeboat Institute (RNLI) crew has been joined by two fire crews and the British Divers Marine Life Rescue in an effort to save the whale.
Videos showed it being hosed down by a man, while a vet performed a check-up at the river’s edge, before the RNLI arrived at the scene to cheers from onlookers at around 9pm.
The whale had been thrashing around in between periods of apparent lifelessness but rescue workers were taking it really steady and cautiously, aware of how distressed the baby whale is.
A crowd of more than 100 people gathered to watch, and there are efforts to keep water flowing onto the whale’s blowhole, to keep it alive until it can be re-floated.
Just after 10pm, rescuers were putting the whale onto an inflatable dinghy and the whale’s tail could be seen thrashing a little.
It is a race against time to get it to safety as soon as possible.
Julia Cable, national coordinator for British Divers Marine Life Rescue, told Sky News: "It’s surprising that no one spotted the whale on its journey to Richmond Lock.
"We do not know how long it has been trapped here but was spotted at 7.30pm.
"The nutritional condition of the whale is fairly poor. He or she isn’t nicely rounded like a whale should be, so it’s nutritionally compromised.
"There’s also damage to the pectoral fins, from stranding, and the fin is showing signs that perhaps it was stranded somewhere earlier in the day as well. But it’s now comfortable and the breathing rate is low.
"We have sent pictures to the vet so we can get further advice on what to do next."
Later, Ms Cable added: "As the tide comes in, we are moving the whale to a safer location, and liaising with the Port of London Authority to decide how to next proceed.
"We are also talking to vets to gain advice on the welfare of the whale"
Jake Manketo, 20, from Richmond, said: "Everyone here is just hoping they get it out.
"We couldn’t believe our eyes when we first saw the poor fella, not every day something like this happens in Richmond."
A spokesman for the Port of London Authority, which owns and operates the lock, said: "At around 7pm on Sunday, a small whale, approximately 3-4m long, believed to be a minke whale, became stranded at Richmond Lock and Weir.
"PLA staff have attempted to assist the whale with water along with British Divers Marine Life Rescue.
"The whale is still alive and the Metropolitan Police are working to keep the public away from the water’s edge."
Minke whales are the smallest of the great whales, growing to about 10 metres.
They can usually be found throughout the northern Atlantic and Pacific Oceans.