Bonhams has withdrawn an ancient Greek drinking vessel from sale amid accusations that it was excavated illegally and that major auction-houses are failing to make adequate checks into whether antiquities were looted from their country of origin.

Archaeologist Christos Tsirogiannis alerted Interpol and other police authorities after producing evidence linking the Bonhams antiquity to convicted traffickers in stolen artefacts. He described the case as yet another example of auction-houses worldwide not taking “basic steps” in tracing an artefact’s history.

This is not the first time Bonham has been forced to pull an artifact for this reason and because of Tsirogiannis's investigative work. Back in 2014, Bonhams withdrew a Roman marble head of Hermes after Tsirogiannis provided evidence of links to Gianfranco Becchina, who was convicted in 2011 in Italy of dealing in illegal antiquities.

Bonhams withdrew the head, which was estimated at $17,000–25,000 at the request of Greece’s Directorate of Documentation and Protection of Cultural Property of the Ministry of Culture and Sport. The work was displayed in seized photographs showing a possible origin and illegal export from Greece. Dr. Christos Tsirogiannis, back then a research assistant with the Trafficking Culture Project, at the University of Glasgow in Scotland, turned up pictures that were posted on ARCA showing the image in the so-called “Becchina Archives,” a collection of photos and documents confiscated by Italian and Swiss authorities in 2002 and 2005. The archives were particularly damning as they laid out the scope and extent of Becchina’s trade in looted objects. Tsirogiannis wrote to David Gill of Looted Matters:

"The origins of the head is Greece, because it is a Greek looter named Costas Gaitanis…who sent to Becchina on May 29th, 1987, the Polaroids depicting the head."

The details surrounding this current withdraw aren't yet clear.