Britain's Ministry of Defence has revived a World War II-era information campaign to warn its military personnel to be careful what they divulge on Facebook, a spokeswoman said Wednesday.
"Careless Talk Costs Lives" was a famous poster campaign launched in 1940 showing people chatting in everyday situations such as on a bus or in a telephone booth, not noticing caricatures of Hitler listening to their conversations.
Fast forward to 2011, and the Ministry of Defence has launched a similar campaign with YouTube videos to warn service personnel of the dangers of putting information about themselves or operations on social networking sites.
The enemy this time is a gun-toting terrorist in a black balaclava.
The campaign is in response to concerns that the armed forces are putting themselves at personal risk by posting where they hang out or live, or are jeopardising operations by revealing the deployments of ships or aircraft.
"There have been incidents where things have been posted or it has had a knock-on effect, but I'm not going to go into specifics," the spokeswoman said.
One YouTube video shows a mother receiving a Facebook message from her son in Afghanistan, where he describes a visit by a VIP to his forward operating base. She reposts the message, and is later shown having tea with a terrorist.
"Social media has enabled our personnel to stay in touch with their families and their friends no matter where they are in the world," said military spokesman Major General John Lorimer in a statement.
"We want our men and women to embrace the use of sites like Twitter, Facebook, LinkedIn and YouTube, but also want them to be aware of the risks that sharing too much information may pose.
"You don't always know who else is watching in cyberspace."
Britain currently has about 9,500 troops in Afghanistan, and British forces are involved in air strikes against Libya.