The graffiti was first reported by a passer by on social media on Monday 11 June.
It followed the discovery of nearly 70 swastikas painted on a German bunker in Jersey over the weekend, some time between 18:00 on Friday, and 08:00 on Sunday morning.
Pictured: Graffiti found at Noirmont in Jersey
As reported by Express in Jersey, that graffiti is being investigated by States of Jersey Police.
Meanwhile, Guernsey Police are also investigating the appearance of red graffiti on the electric substation on Les Effards Road, St Sampson. It occurred some time overnight between Sunday 10 June and Monday 11 June.
Pictured top: Graffiti discovered in Guernsey