BAGHDAD (AP) — An Iraqi court Sunday postponed the trial of two European tourists charged with antiquities smuggling after their lawyers argued more information was needed about the ancient shards found in their possession.

The defense team for German national Volker Waldman filed a motion in court saying there was insufficient information about the value of the pieces Iraqi officials found on him. He was charged alongside Jim Fitton, 66, a retired British geologist.

Baghdad’s felony court postponed the case until June 6.

Furat Kubba, defense lawyer for Waldman, said he launched the motion partly to seek more information about the historical significance of the pieces found in his client’s possession.

A government technical team concluded the items — 10 pieces found in Fitton’s possession and two in Waldman’s — could be classified as archaeological pieces because they dated back more than 200 years. The shards, some as small as a fingernail, were collected at Eridu, an ancient Mesopotamian city in southern Iraq.

Waldman’s defense team has said the German tourist had been carrying the pieces for Fitton but that he did not pick them up from the site. Both men are charged with smuggling based on the country’s antiquities laws, and could potentially face the death penalty. However, officials have said that was only a remote possibility.

Kubba said they would seek to have Waldman and Fitton tried separately. Both men said they were unaware of the Iraqi antiquities smuggling law or that there would be penalties for picking up or attempting to leave the country with the items.

Fitton and Waldman were arrested on March 20 at Baghdad International Airport when airport security discovered the items in their luggage. They had been part of a tourism expedition across the country’s ancient sites. Their case has received international attention at a time when Iraq hopes to boost its nascent tourism sector.