Vandals targeted the roof of the listed building
A historic landmark in Newcastle has been targeted by graffiti vandals.
The damage to the roof Bessie Surtees House means a significant clean-up bill for English heritage, which uses the quayside site as its North East base.
The two five-storey 16th Century merchants' houses are considered some of the best examples of Jacobean domestic architecture in the country.
Police investigating the damage have released images of the tags, which read "LG", "GRIM" and "KAME".
A spokesman for Northumbria Police said: "The damage was caused to a Grade II-listed building which is an important and much-loved part of Newcastle's history.
"The people that have done this are nothing but mindless vandals and what they've done amounts to criminal damage.
"We have made inquiries and are aware that these are tags that have appeared in other areas of the city centre.
"Whoever it is, or they are, is making the city look unsightly and untidy and it's imperative we put a stop to it.
"They've already caused a significant amount of damage, both to buildings and subsequently financially, and we need to stop them before they do any more."
English Heritage said it was working with the police to find those responsible.