British police seized all the items in an operation that March. Soon, the State Council, China's Cabinet, set up a special cross-departmental working group to bring them home.

In 1998, over 3,000 relics were returned to China after cooperation by law enforcement units, a lawsuit and negotiations. It was the largest single repatriation of lost cultural relics in the history of New China.

However, a local buyer of dozens of remaining relics refused to take part in negotiations, and the civil dispute dragged on after hitting a deadlock. The 68 relics remained impounded by British police.

"But we never stopped working on the case and stayed in close contact with the embassy and the British side to follow up on their latest information," Guan said.