Victoria’s education department is investigating after a state school employee brought a “Fuhrer cake” into a history class and let his students play with replica firearms and other Nazi paraphernalia.

Facebook posts provided to the Anti-Defamation Commission by a member of the public show one student at Dromana secondary college wearing a Nazi hat, and others playing with replica weapons – including a Zyklon B poison gas canister used in the Holocaust – during a second world war history class.

The ‘Fuhrer cake’ made by an employee of a state school in Victoria.

The posts suggest the employee – who was not a teacher at the school – had brought in items from his own personal collection. The man was a member of a Facebook group that trades military items, according to Fairfax Media, which first reported the story.

Students are also shown posing with rifles, helmets and uniforms used by Australian troops. In one Facebook post, the employee describes making a “Fuhrer cake” after watching a documentary about Hitler’s maid.

“I’ll take a photo later to show how it turns out, if I start talking in German and growing a little moustache under my nose after eating it i’ll put out a warning!” he wrote.

He then posted a picture of the cake, which was decorated with a swastika made out of apple slices, before later writing he had “brought in the rest of the Fuhrer cake I made sat night (into class), so we talked war and ate cake”.

“I did a bit of artistic licence on the look but I’m really pleased it was brilliant with cream drizzled on it,” he added. “No wonder it was Hitler’s favourite cake.”

Fairfax reported that the swastika was not visible when the leftover cake was brought into the class.

A department spokeswoman confirmed an investigation into the use of “some inappropriate items” at the school, one hour south of Melbourne, describing the incident as a “serious error of judgment”.

“The actions of the Nazis were abhorrent and should not be forgotten by any generation,” the spokeswoman said. “Using symbols or artifacts in a way that may normalise or trivialise the actions of the Nazis is completely unacceptable.”

A student with military memorabilia.

The Anti-Defamation Commission, a Jewish organisation set up to combat antisemitism, said it was “shocked and heartbroken”.

“The Holocaust, in which six million Jews and millions of others were systemically murdered, should not be the subject for funny games, entertainment and dress-up,” its chairman, Dvir Abramovich, said.

In a statement, Dromana secondary college’s principal, Alan Marr, apologised for “any impact this incident may have had on our students or any distress it may have caused to members of the community”.

“Unfortunately we have been made aware of an incident that does not live up to the standards that we expect of our staff and we are taking immediate steps to investigate what happened and take appropriate action,” he said.

“The intent of the history lesson was to educate students about the impact of World War II but some of the items brought into the class were entirely inappropriate.”