Red fabric has been pinned across the Westbury White Horse on Salisbury Plain to form the St George's Cross, English Heritage said, as a campaign to display English and Union flags in public places continues across the country.

A spokesperson for English Heritage said the organisation was aware that "red fabric has been attached to the Westbury White Horse" and that staff would remove the material "as soon as we can and see whether the pegs that were used have caused any damage to this much-loved historic landmark." Wiltshire Police said it was not treating the incident as a criminal matter. A force spokesman said: "No criminal offences are thought to have been committed and we are not investigating it."

Local residents described the alteration as patriotic rather than damaging. Regular walker Velisa Russell told reporters: "Luckily there's no damage as red material was used. It's more an act of patriotism, not vandalism. Just a bit of fun." The hill figure, measuring about 53 metres, was first cut into the escarpment in the late 17th century and was reshaped into its current form in 1778.

The alteration at Westbury comes amid a broader wave of activity sometimes called "Operation Raise the Colours" or "Operation Flying the Colours," in which people have draped St George's and Union flags across town centres, affixed flags to public infrastructure and painted crosses on roundabouts and road signs. Councils in some areas, including Tower Hamlets and Birmingham, have taken down banners from council-owned lampposts and removed markings and graffiti, citing health and safety and the cost of reinstating public surfaces.

The campaign has divided opinion. Some Conservative politicians and supporters have publicly endorsed the displays as expressions of national pride. Shadow Justice Secretary Robert Jenrick was among those who hung flags in public spaces, and former minister Kemi Badenoch wrote that flags were being flown as "symbols of unity, nationhood and optimism," saying that pride in the country was not racist.

At the same time, organisers and imagery associated with the campaign have been seized upon by far-right figures. The campaign was co-founded by Andrew Currien, also known as Andy Saxon, who has been described as an ally of Stephen Yaxley-Lennon, also known as Tommy Robinson. Organisers have accepted a donation of flags from Britain First; the group has repeatedly denied accusations that it is a far‑right or fascist organisation. Robinson and other far‑right activists have expressed support for the flag‑raising efforts, which has fuelled concerns among opponents who say the displays are being used for divisive ends.

Downing Street has defended the flying of flags as an expression of patriotism. The prime minister told BBC Radio 5 Live that he was "very encouraging of flags," calling them "patriotic" and "a great symbol of our nation," while warning that their use for "purely divisive purposes" can devalue them. Critics have argued for clearer distinctions between harmless displays of national pride and activity that may be exploited by extremist groups.

English Heritage said its priority was to preserve the landmark and to assess any potential damage from the pegs used to secure the fabric. Wiltshire Police reiterated that it did not believe criminal offences had been committed in the alteration of the hill figure.

The Westbury White Horse is among nearly 400 historic sites for which English Heritage is responsible. The organisation has previously urged the public to respect protected landscapes and monuments while acknowledging that patriotic displays can be a legitimate form of expression. Officials will remove the fabric from the hill figure once access and safety checks allow and will assess the site for any restoration work that may be required.