BARABOO, Wis. — Authorities are trying to determine who posted anti-Semitic fliers ahead of planned meetings next week over a photograph of Wisconsin high school boys appearing to give a Nazi salute.

The fliers were posted Monday on the exterior of Jack Young Middle School in Baraboo. They contained warnings about Dec. 18, an apparent reference to a day of high school assemblies featuring speakers calling for tolerance.

The Baraboo News Republic reported that authorities also are looking into an anti-Semitic online video satirizing the photo and warning viewers to stay home Dec. 18.

The photo was taken last spring outside the Sauk County Courthouse in Baraboo.