Greek officials vowed on Tuesday to track the people behind the filming of a gay sex scene on the Acropolis of Athens, the country’s most important archaeological site, after footage emerged online.

A culture ministry spokesman said that they had launched an investigation into the video, which shows a sexual encounter between two masked men at the UNESCO-listed site.

They wanted to “find as soon as possible those responsible for this illegal shoot”, said the spokesman.

The anonymous producers of the short film called Departhenon said the Parthenon symbolised “nationalism, the cult of Antiquity” and “patriarchy”.

They described the erotic scene between the two men at the site as a “political act”.

But a statement last Friday from the culture ministry said: “The archaeological site of the Acropolis does not lend itself to activism or any other action that offends or shows a lack of respect to the monument.”

The 36-minute film was first shown to a small audience on December 16 at the University of Thessaloniki in the north of the country without provoking an outcry.

It was its appearance online last Friday that sparked the backlash.

“As a Greek, I’m ashamed,” the president of the Greek Actors’ Association, Spyros Bibilas, told broadcaster ANT1.

“You can’t do anything and everything in the name of activism.”

The union representing those guarding the country’s museums and archaeological sites expressed its “outrage and shame” over what it called a “vile film”.

Heading off questions regarding the level of surveillance of such sites, it said they suffered staffing problems because the finance ministry “almost never approves the recruitment of guards”.

The University of Thessaloniki, which did not inform the culture ministry of the film’s contents, risks being caught up in the investigation. It has not offered any reaction to the controversy.

“The Acropolis and its monuments are universal symbols of the classical spirit and civilization and form the greatest architectural and artistic complex bequeathed by Greek Antiquity to the world,” says the UNESCO listing for the site.

It is also the country’s most visited landmark.