(RNS) Prominent Muslim leaders who toured Nazi concentration camps last summer marked International Holocaust Remembrance Day by decrying attempts to deny the Holocaust that killed 6 million Jews.

“We condemn any attempts to deny this historical reality and declare such denials or any justification of this tragedy as against the Islamic code of ethics,” the leaders wrote in a joint statement issued Thursday (Jan. 27).

Signatories included Imam Mohamed Magid, president of the Islamic Society of North America; Sayyid M. Syeed of the Islamic Society of North America; and Laila Mohammed, daughter of the late Imam Warith Deen Mohammed, who once led but later disbanded the Nation of Islam.

The leaders condemned “anti-Semitism in any form” and called for people of faith to “stand together for truth.”

“Together, we pledge to make real the commitment of `never again’ and to stand united against injustice wherever it may be found in the world today,” they concluded.

Their trip in August to Dachau and Auschwitz also was organized to demonstrate their opposition to Holocaust denial.