The owners of a four-star hotel in Austria are suing a German visitor for defamation after he complained online about a photo of a “Nazi grandpa” in a swastika-adorned uniform hanging on the wall, according to a report.

The guest, identified in court papers as Thomas K, posted his complaint on Booking.com and TripAdvisor under the heading: “At the entrance they display a picture of a Nazi grandpa,” the Guardian said.

The man and his wife had visited the hotel in the village of Gerlos in the Tyrolean Alps in August 2018.

Thomas took notice of the photo when he and his wife checked into the hotel, which was not named.

“This made us wonder what the hotel owners are trying to tell us with this image. This incident speaks volumes about the current state of affairs in this region of Austria. Sadly, our desire to visit this mountain region has disappeared completely,” the man wrote in the online review, according to the news outlet.

The owners of the hotel then contacted both sites asking for the reviews to be taken down on the grounds that the “Nazi grandpa” description was libelous and defamatory, since the man was not a member of the Nazi party, the site reported. He was one of the owner’s grandfathers.

The relative was a member of the Wehrmacht, the armed forces of Nazi Germany, the owners claimed.

TripAdvisor had initially declined to remove the post, but both sites have since taken it down, according to the Guardian.

The owners of the hotel were able to identify Thomas by matching his booking number to the review, and they filed a lawsuit against him in a regional court in Innsbruck, Austria.

According to the news outlet, Thomas researched the identity of the man in the photograph at the German National Archives in Berlin and confirmed that he did join the Nazi party in 1941 and 1943.

Nonetheless, the Innsbruck court awarded the hotel owners round one in the dispute, ruling that Thomas’s review implied that the owners sympathized with National Socialist ideas, according to the Guardian. The trial is expected to continue until later in the year.

Meanwhile, a lawyer for the hotel owners said the photograph in question has since been taken down from the walls of the inn.