Swiss police have blocked an Internet auction of a 4,000-year-old clay tablet that authorities say was "most probably" taken from Iraq.

Swiss federal police said Tuesday they brought criminal proceedings against a vendor identified only as a resident of Zurich.

Authorities say the sale on eBay, the global internet auction web site, was stopped last week, just moments before bidding closed on the artifact. It was not clear Tuesday whether any bids had been made.

Swiss officials said a German archaeologist spotted the artifact on eBay's web site and alerted Swiss authorities.

The Iraqi National Museum was looted in 2003, shortly after the U.S.-led invasion that toppled the regime of Saddam Hussein. Many ancient treasures have been returned, but the facility remains closed for security reasons.

Some information for this report was provided by AFP, AP.