A "terrible mistake" involving the publication of convicted murderer Russell Williams's photo in a Department of National Defence booklet has prompted an apology from Ottawa.

Lt-Gen. André Deschamps addresses a classroom. Russell Williams is seated in the front row of senior officers, on the right. (DND)

In a statement issued Wednesday evening, Minister of National Defence Peter MacKay said he "immediately ordered the military to destroy all copies of the collected booklets" as soon as he became aware of their existence.

Melanie Villeneuve, a spokeswoman for the Forces, said via email that the the photo in question depicted Lt-Gen. André Deschamps addressing a classroom, with Williams seated in a front row of senior officers.

The image appeared in the 2012 CF Canadian Defence Academy publication, which Villeneuve said is designed “to reinforce the profession of arms to all CF personnel and to emphasize the commitment, both institutional and personal, to continuous learning and professional development.”

Villeneuve said the booklet was distributed only within the Canadian Defence Academy headquarters before the image of Williams was discovered. The majority of the copies were recalled and destroyed, but a few copies have not been returned, Villeneuve noted.

The initial print run of 4,000 copies had a cost of $5,000 and the revised version will cost a similar amount to print.

Williams, a former decorated commander of Canadian Forces Base Trenton, is serving two life terms with no chance of parole for the brutal rapes and murders of Jessica Lloyd and Canadian Forces Cpl. Marie-France Comeau.

He pleaded guilty to 88 charges and was sentenced in October 2010.

MacKay offered his public apologies to the victims' families on Wednesday and said he also planned to follow up personally, on behalf of the entire Canadian Forces.

"I intend to call the families of Mr. Williams' two murder victims to inform them of this terrible mistake and express our most sincere apologies on behalf of the entire military family," MacKay said in his statement.

An investigation is underway by the department to ensure a similar incident does not happen again, MacKay said.