Firefighters in North Wales are currently tackling a large fire at the old North Wales hospital in Denbighshire.
Crews were called to the former mental asylum at 3am on Friday morning.
It's thought as many as 40 firefighters are at the scene.
People are being told to avoid the area.
The site has seen attacks by arsonists several times in the past, most recently in February.
In April there were claims an illegal rave had been planned at the site.
The cause of the fire is not yet known.