A former manager of the Valtice Castle, a baroque UNESCO Heritage Site in the Czech Republic, has become the main suspect in a police investigation into the disappearance of 58 paintings left in the castle’s care, Der Standard reports.

The South Moravian castle is home to an annual art show titled “Large Format.” The last edition hosted artists from six countries, and 39 of them are now missing their artworks. The combined value of the 58 missing paintings is estimated at €170,000 ($185,000).

The castle manager initially told police detectives that the artworks had disappeared. Police thus first searched for a gang of art robbers. “We had expected to find an organized ring of art looters who’d sell the artwork in Prague and abroad,” a Czech police spokesperson told the media.

Instead, police found broken frames and partially burnt canvases, and suspicion quickly switched to the castle manager himself. The manager claims not to have known what the paintings were worth. The motives remain mysterious.

One of the missing paintings is a work titled “Madonna Carried by Ants” by Czech composer and painter Vladimír Franz, better known as the fully-tattooed arts professor who polled third in the 2013 Czech presidential election.