In the latest issue of Al Qaeda in Yemen's English-language magazine, "Inspire," the group celebrates the 10th anniversary of the 9/11 attacks, CBS News reports.
The cover of the issue reads "The Greatest Special Operation of all time."
The issue includes an apparent quote from Al Qaeda founder Osama bin Laden, who was killed in May by U.S. Special Forces. Bin Laden urged his followers not to be discouraged by America's status as a superpower.
"Do not let America's front and its troops seem hard and become great in your eyes, as we have struck them repeatedly and they were defeated frequently and they are the most cowardly at the time of encounter," bin Laden said.
The BBC reports that the issue also accuses Iranian President Mahmoud Ahmadinejad of spreading "conspiracy theories" about the 9/11 attacks. Ahmadinejad's speech at the United Nations last week is described as "ridiculous."
"The Iranian government has professed on the tongue of its president Ahmadinejad that it does not believe that al Qaeda was behind 9/11 but rather, the U.S. government," an article says, according to ABC News. "So we may ask the question: why would Iran ascribe to such a ridiculous belief that stands in the face of all logic and evidence?"
The article accuses Iran of trying to compete with Al Qaeda.
"For them, al Qaeda was a competitor for the hearts and minds of the disenfranchised Muslims around the world," the article says. "Al Qaeda... succeeded in what Iran couldn't. Therefore it was necessary for the Iranians to discredit 9/11 and what better way to do so? Conspiracy theories."
CBS News reports that one article, written by Yahya Ibrahim, looks at the effects of 9/11 ten years later.
"Ten years from 9/11 and the mujahidin have spread out from Afghanistan to Pakistan, Yemen, Somalia, North Africa and God willing the list will grow and the proliferation of jihad will continue," Ibrahim wrote.