Japanese traders are selling ivory tusks to Chinese buyers in Japan, knowing that they will be illegally exported to China, an international conservation group said Thursday as it screened an undercover video showing the transactions.

The video, taken by the U.S.-based Environmental Investigation Agency, showed an undercover EIA investigator who presented himself as a Chinese buyer and secretly filmed ivory traders in four Japanese prefectures — Chiba, Gifu, Osaka and Shizuoka — last December.

The video suggested that Japanese traders are suppliers of illegal ivory to China.

In the video, a trader in Hamamatsu, Shizuoka Prefecture, is filmed saying, "(Chinese) customers are always bringing back (tusks) through their own routes." The trader apparently knows the tusks would be illegally exported to China.

Another trader in Gifu is filmed saying, "I don't care if it is illegal. I am going to obtain another three (tusks)."

EIA President Allan Thornton said Japanese ivory markets and the government's sloppy measures have led to the slaughter and illegal exploitation of African elephants.

Thornton said Japan should follow the United States, China and Hong Kong and ban the domestic ivory trade.