A leading Jewish human rights group has denounced popular K-pop band BTS, whose live performance on Japanese TV was canceled last week, over a T-shirt mocking victims of the atomic bombing of Japan while also claiming that a photo shoot had shown them wearing hats with a Nazi logo.

The Los Angeles-based Simon Wiesenthal Center blasted BTS in a statement released Sunday.

“Wearing a T-shirt in Japan mocking the victims of the Nagasaki A-bomb, is just the latest incident of this band mocking the past,” Rabbi Abraham Cooper, associate dean and director of global social action with the center, said in a statement.

The statement charged that members of the band had posed for a photo shoot wearing hats with the Nazi SS death head logo, citing pictures believed to be from January 2015, and flags that appeared on stage at one of their concerts that the center said were “eerily similar” to the Nazi swastika.

The SS was a key component of the Nazi mass murder of 6 million Jews during the Holocaust.

“It goes without saying that this group, which was invited to speak at the U.N., owes the people of Japan and the victims of the Nazism an apology,” Cooper said.

“But that is not enough,” he added. “It is clear that those designing and promoting this group’s career are too comfortable with denigrating the memory of the past. The result is that … young generations in Korea and around the world are more likely to identify bigotry and intolerance as being ‘cool’ and help erase the lessons of history. The management of this group, not only the front performers, should publicly apologize.”

TV Asahi Corp. said Thursday it had canceled a live performance by BTS amid a furor over a member having worn a controversial T-shirt, said by some to celebrate the use of atomic weapons against Japan during World War II.

The controversy erupted over photos of BTS member Jimin wearing the T-shirt, which commemorates the day the Korean Peninsula was liberated from Japanese colonial rule in 1945. But the design, which has drawn flak from many Japanese, also includes a photo of an atomic bomb exploding over Japan.

For its part, the chart-topping band apologized in a statement to its Japanese fans for not being able to make the appearance, without elaborating.

The incident comes as ties between Tokyo and Seoul have once again soured over historical issues.

The latest controversy follows a recent decision handed down by South Korea’s Supreme Court that ruled Japanese firms can be held liable for forced labor that occurred before and during World War II.