The latest artwork to be unveiled from Banksy has been defaced by a man wearing a black balaclava just hours after it went up.

The street artist’s latest piece, a rhino mounting a silver Nissan Micra with a traffic cone on its bonnet, was revealed on Monday and a video obtained by BBC News shows a man walking up to the artwork and spray painting it, leaving a white tag on it.

The crowd gathered at the piece, on Westmoor Street in Charlton, south-east London, are heard saying “Don’t do that” and as the person walks away, a voice from the crowd asks “Why did you do that? Why did you do it?”

Banksy has been posting artwork to his Instagram around 1pm every day since August 5.

The rhino follows Sunday’s artwork, piranhas on a police sentry box, which has now been removed from near London’s Old Bailey court to preserve it.

The anonymous artist appeared to have used translucent spray paint to turn the box into a giant fish tank for the piece which appeared on Ludgate Hill before being taped off by the local council.

The glass-paned box will be kept temporarily by the City of London Corporation’s offices, a walk of less than 15 minutes from the previous location.

A spokesman for the authority said: “We have moved the artwork to Guildhall Yard to ensure it is properly protected and open for the public to view safely.

“A permanent home for the piece will be decided in due course.”

Banksy’s first piece was a goat perched on top of a wall and has been followed by silhouettes of elephants, monkeys, a wolf, pelicans, and a cat, all of which have popped up in various locations across London.

The sixth piece, a stretching cat on an empty, distressed advertising hoarding, was removed from its location in north-west London hours after it was unveiled on Saturday.

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.

The cat design was the second piece to be removed last week after a howling wolf on a satellite dish was taken off the roof of a building in Peckham, south London, less than an hour after it was unveiled.

A spokesperson for Banksy told the PA news agency that the artist was neither connected to nor endorsed the theft of the wolf artwork and that they had “no knowledge as to the dish’s current whereabouts”.

The fifth piece to be unveiled was on Bonners Fish Bar in Walthamstow, east London, and shows a pelican stooping to scoop up a fish on the takeaway’s sign, while another is tossing one in the air.

The fish and chip shop had announced in July that it would close from August 1 until September 5, and a message on its Instagram page expressed their gratitude at the artwork.

It said: “The last few days have been a whirlwind, thank you to all who have sent such kind words, comments and messages.

“We’re so sorry if we haven’t replied, as you can imagine it’s been extremely overwhelming!

“We’re over the moon that Banksy decided to choose our little fish and chip shop in wonderful Walthamstow and love the design.

“Contrary to some beliefs, we didn’t ask him to do this, but are very grateful he did!”