A historic site in Norfolk has been struck by vandals again who have ripped off signs aimed at dissuading dog owners from flouting rules.

Dunston Field, which surrounds Caistor Roman Town, was closed last month to the public to allow sheep a safe space to graze and to prevent dog fouling.

But just days after the field was closed, a padlocked gate was forced open and signs ripped down. 

Norwich Evening News: Signs telling dog walkers to keep their pups on leads and to clear up after them have been ripped down at Caistor Roman Town south of NorwichSigns telling dog walkers to keep their pups on leads and to clear up after them have been ripped down at Caistor Roman Town south of Norwich (Image: Norfolk Archaeological Trust)

It has now happened for a second time amid an ongoing campaign by Norfolk Archaeological Trust, which runs the site, to clamp down on rule-breaking dog owners and make the space "safe for everyone".

Director Natalie Butler said: "It is so frustrating and disappointing for this to happen again.

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"These actions cost the charity time and money."

The space, south of Norwich, is privately owned by the Norfolk Archaeological Trust which said visitors not keeping their dogs on leads or picking up their dog's mess were behind its decision to close the 22-acre field. 

Norwich Evening News: Roman remains at the Caistor St Edmund siteRoman remains at the Caistor St Edmund site (Image: Archant)

Ms Butler added: "Before making the decision we received lots of complaints about dogs off leads from people with some saying they stopped coming because of it. 

"Dogs off leads can be intimidating and with sheep and ground-nesting birds on site it is important to protect their safety and that of visiting school children.

"All we are doing is just trying to make it a nice place to visit and we are very keen to put a stop to whoever is ripping the signs off."

Norwich Evening News: A sign put up by a dog walker after their dog was attacked by anotherA sign put up by a dog walker after their dog was attacked by another (Image: Natalie Butler)

Caistor Roman Town, also known as Venta Icenorum, is a 120-acre site south of Norwich and one of Norfolk's most remarkable archaeological landmarks.

The town was first established in the AD70s as the capital of the Iceni tribe - whose Queen Boudicca led a revolt against the Romans.