PENSHAW Monument has been the target of a second serious graffiti attack in three months.
Political slogans have been sprayed along the front of the Victorian folly in black paint.
The National Trust-owned Monument was targeted at the end of July, when the charity had to shell out more than £1,000 on hiring a specialist clean-up team to undo the damage.
Lyndsay Dixon, from Houghton, spotted the damage.
“Somebody has written ‘Your government is using Ebola as a vile chemical weapon’ and an email address,” she said.
“It is visible from about halfway up the hill. It is disgusting.”
National Trust spokesman Gareth Wilson said the charity faced a hefty bill to clean-up the damage.
The public had stepped in to cover the cost of the clean-up last time, but it was doubtful the same would happen again.
He said: “We will be doing our best to get it removed as soon as possible.
“As a charity, it is extremely disappointing that this has happened again.”
Protecting the Grade I-listed monument required the hiring of specialist cleaners at considerable expense, said Mr Wilson
“It cost us about £1,500 last time. We received donations that more than covered the cost,” he added.
“Whether we will do so again, so soon after the last time seems less unlikely, but we will keep our fingers crossed.”