Robbers of an archaeology museum in the eastern Croatian town Vinkovci ran off with six-kilos-worth of priceless golden artefacts, the Vecernje Novosti daily reported on Tuesday.

The collection stolen over the weekend, including golden coins from the pre-Roman and Roman period, as well as a 5000-year-old medallion, was locked in the museum safe and was never shown to the public because of security concerns, the report said.

“The robber knew what he was looking for and he took what was the most valuable,” said Stjepan Jozic, the director of the museum in Vinkovci, some 150 kilometres east of Zagreb.

Police virtually sealed the building for the investigation. The same museum has been already hit twice by robbers, in 1971 and 1976 - but the perpetrators were never found.