Swastikas have been sprayed on a bench dedicated to D-Day veterans in Twyford Woods, Lincolnshire.
Walls and empty fuel drums in the woods, which were once home to RAF North Witham, where American aircraft took off for Normandy ahead of D-Day, were also graffitied with the Nazi symbol.
Lincolnshire Police said: “A number of areas within the Twyford Woods site have been defaced with swastikas in silver and white spray paint.
“This includes a commemorative bench which has been extensively vandalised.
“We are appealing for witnesses to this vandalism and anyone with any information that can assist with our investigation.”