A central London glass police box has been made to look like a tank of piranhas, in the seventh in series of works by the graffiti artist Banksy.
The elusive artist claimed the work as his own by featuring it on his Instagram account in a post at 1pm on Sunday.
The fish depicted on the police box are different in style from the previous six silhouetted designs that Banksy has claimed as his work on successive days over the past week.
One of the designs, featuring a wolf on a satellite dish, was removed by suspected thieves. Another of a stretching cat on an empty billboard was removed by contractors.
Two City of London police officers were initially seen examining Banksy’s new work before taking pictures. One officer told PA Media news agency they were asked to inspect the artwork after it was picked up on CCTV cameras, and that they were waiting to hear what would be done about it.
The governing body of the City of London later said it was working on options to “preserve” the new Banksy artwork that appeared on Sunday.
A City of London Corporation spokesperson said in a statement: “We’re aware of the works on the City of London police box on Ludgate Hill. We are currently working through options to preserve the artwork.”
Banksy’s Instagram account has revealed a new animal artwork each day for the past seven days. They have featured silhouettes of a goat, elephants, monkeys, a wolf, pelicans and a cat.
On Saturday, a piece showing a stretching cat on a damaged and empty advertising billboard was removed from its location in north-west London hours after it was revealed.
Crowds booed as the piece in Cricklewood was dismantled by three men who said they were hired by a contracting company to take down the billboard for safety reasons.
Hours after Banksy confirmed the design was his, crowds gathered from across London to see the piece before the men arrived.
A contractor, who only wanted to give his name as Marc, said they were going to take the billboard down on Monday and replace it, but the removal had been brought forward to Saturday in case someone ripped it down and left it unsafe.
A black board was first used to cover most of the cat at the request of the police, who wanted to stop people walking in the road in front of traffic.
The owner of the billboard has told police he will donate it to an art gallery.
The cat design was the second piece to be removed during the week after a painting of a howling wolf on a satellite dish was taken off the roof of a shop in Peckham, south London, less than an hour after it was unveiled.
“It’s a great shame we can’t have nice things and it’s a shame it couldn’t have lasted more than an hour,” a witness said.
The first piece of graffiti in Banksy’s animal-themed series, which was announced on Monday, is near Kew Bridge in south-west London and shows a goat with rocks falling down below it, just above a CCTV camera.
On Tuesday, the artist added silhouettes of two elephants with their trunks stretched towards each other on the side of a building in Chelsea, west London.
This was followed by three monkeys that seemed to swing underneath a bridge over Brick Lane, east London.
The fifth design, of pelicans pinching fish from a London chip shop sign in Walthamstow, north-east London, was revealed on Friday.
The Observer reported on Saturday that the series was designed to cheer up the public during a period when the news headlines had been bleak. Banksy’s support organisation, Pest Control Office, indicated that theorising about the deeper significance of each new image had been way too involved and the works had instead simply been designed to give people a moment of unexpected amusement.