Firefighters have had to tackle a large fire at the Crumlin Road Courthouse in Belfast which they say was started deliberately.
Four appliances, 20 firefighters and an aerial appliance were called to the scene shortly before 3am on Monday.
The fire was burning inside in the old courtroom.
NI Fire & Rescue Service say they had to position an appliance behind the courthouse, in the Shankill Estate, to protect houses from hot embers caused by the blaze.
Police are investigating the incident as an arson attack and are appealing for anyone with information to contact them on 101.
The fire has since been extinguished.
DUP alderman Brian Kingston said it was tragic that more of the historic building had been damaged.
“The building had already been damaged by previous fires and I fear that little of the original content will now be left,” he said.
“There are reports locally of young people having been on the site over this past weekend, whether or not that is connected to the fire. I would appeal for anyone with relevant information to pass that on to the PSNI.”
Mr Kingston added: “This historic and distinctive courthouse, designed by Charles Lanyon, is an architectural jewel for Belfast and was in use for almost 150 years until it closed in 1998.
“It would be a tragedy if this fine listed building were to be lost.”