TOKYO — Meat from whales killed as part of Japan’s “scientific” hunt was served last year in upscale sushi restaurants in Los Angeles and Seoul, according to a DNA analysis published Wednesday.

A global ban on whaling was imposed 14 years ago, but Japan has courted controversy for years by invoking an exception in the ban for scientific research and by dispatching a whaling fleet that harpoons several hundred whales a year. The fleet brings home thousands of tons of whale meat that are sold across Japan, but which cannot legally be sold to buyers in the United States or South Korea.

In what may prove to be a major embarrassment to the Japanese government, the peer-reviewed DNA analysis suggests that distribution of whale meat may be haphazardly managed and could be flowing into an international smuggling ring.

The analysis showed two pieces of whale meat sold in October in a Los Angeles area restaurant were “identical” to whale products bought in Japan.