Lead thieves have caused £250,000 damage to a 150-year-old mansion in Rochdale.
Developers have warned that Honresfeld, in Littleborough, has been targeted at least 20 times in the last six months, and is under "constant threat".
The majority of the damage has been done the roof, but thieves have also stolen copper piping, wiring and brass fixtures and fittings from inside the 26-bedroom home.
Antique parquet floors have also been damaged due to water leaking inside.
The property, most recently a care home, has been empty since 2016.
The most recent theft occurred last Tuesday, when yet more lead was stripped from the roof.
Developers plan to convert it back into a family home while also building eight new houses in the grounds.
They say surveyors have estimated repairs will cost about £250,000.
Chris Grieves, of Hallmark Properties, says the building is "under serious and constant threat" from both the thieves and weather exposure.
Security has been added to the site.
The developers have also taken the unusual step of putting up signs highlighting the extent of the damage in a bid to deter further thefts.
The signs show different images of the damage caused and include messages such as ‘Thieves, this is the damage you have caused to this historically important building'.