The Canadian military says it has taken what may be an unprecedented step by burning the uniforms of former colonel Russell Williams who was convicted of murder and sexual assault.

Cmdr. Hubert Genest said Friday that Williams's clothes were burned the previous day at CFB Trenton — Canada's largest military airbase which Williams once commanded.

Williams was sentenced last month to life in prison after pleading guilty to murdering two women and raping two others.

Genest says uniforms are usually retrieved when someone leaves the military. He says Williams' clothing was burned because much of it had his name on it.

Williams was once a rising star in the military who flew prime ministers and served as a pilot to Britain's Queen Elizabeth II during a 2005 visit.