Chester's ancient Roman walls have been vandalised with graffiti.
Cheshire Police said a witness reported "four women spraying white paint" on the walls just after 4.30pm on Monday.
Officers from the force's Rural Crime Team found a section of the walls near the cathedral tagged with graffiti which included the names "Jasmine", "Paris", and "Lilly".
PC Jono Lightfoot said the walls had "very strict" protections in law as both a Scheduled Monument and World Heritage site.
He said: "Spraying paint like this on the historic fabric causes damage to the stone and It also costs a lot of money to remove.
"This type of incident is a heritage crime and will not be tolerated."
Anyone with any information in relation to the latest incident is asked to contact Cheshire Police via the website, or on 101, quoting IML-2285695.
In January, a different section of the historic walls were daubed with paint.
A witness said she saw 'four women' spraying white paint on the historic Roman walls
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Vandals sprayed the walls sometime between 3pm on January 7 and 1.30pm on January 8.
The section of wall between Water Tower Gardens and Pemberton's Parlour was sprayed with a tag reading "Glory".
PC Jamie Ho, of Chester City Beat Team, said: "Chester City Walls are a scheduled monument of national importance, as Britain's oldest, longest, and most complete circuit of defensive walls.
"The local authority works hard to maintain the walls, which attract thousands of people to our city every year, so it’s disappointing to see that some people feel it’s acceptable to spray them with graffiti.
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PICTURED: Graffiti on a different section of the walls dating to January of this year
|CHESHIRE POLICE
"Enquiries are ongoing and I would urge anyone with any information in relation to the incident to come forward so the person responsible can be held accountable."
The walls, which are considered to be a World Heritage site, are believed to be over 2,000 years old and build to defend a fort known as Deva Victrix.
The Roman walls are considered to be the longest and most complete Roman and medieval town walls in Britain.
Originally constructed between 70 and 80 AD, they were later expanded by the Normans, then further fortified before the Civil War.
PICTURED: A section of original Roman wall along the Chester Canal
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A section of the historic Chester walls was breached during the Civil War
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The full walls were complete around the 12th century, and almost every section of the walls is Grade I listed.
Conservation of the walls has been an ongoing project, with a part of the wall collapsing in 2008.
In January 2020, another section of wall collapsed while development work was being carried out nearby.