Al Qaeda No 2 Ayman al-Zawahri has responded to criticism about the organisation’s notoriously brutal tactics, maintaining that it does not kill innocents, in hour-and-a half-long audio response to questions submitted to the movement on extremist websites.

Zawahri also addressed the issue of Al Qaeda’s founder, Osama bin Laden, assuring supporters that the reclusive leader was in good health. “Sheik Osama bin Laden is healthy and well, by the grace of Allah,” he said, while noting he would not be there forever. “He must die one day, whereas Allah’s religion will remain.”

The audio message, which was accompanied on Wednesday by a 46-page English transcript, was the first installment of answers to a raft of online questions and focused mainly on future al-Qaeda efforts elsewhere in the region, particularly Egypt.

“We haven’t killed the innocents, not in Baghdad nor in Morocco, nor in Algeria, nor anywhere else,” he said according to the English transcript which, like the audio message, appeared on websites linked to the group.

The answer was in response to the question “excuse me, Mr Zawahri, but who is it who is killing with Your Excellency’s blessing the innocents in Baghdad, Morocco and Algeria?”

Al Qaeda has taken credit for the destruction of the World Trade Center which killed nearly 3,000 people in New York City in 2001, while its affiliates in Iraq, Afghanistan and Algeria regularly set off explosives in crowded urban areas.