The Ministry of Defence has issued ‘careless talk costs lives’-style videos warning servicemen and women about the security risks of social networking websites.

In one of the clips released on YouTube, a mother posts a message on Facebook about her airman son who is serving in Afghanistan.

He makes the first faux pas by sending a message about a VIP visiting his base – which she duly shares with all her friends.

Then the doorbell rings and a man wearing a balaclava, camouflage gear and crossed bandoliers comes in and drinks a cup of tea as she shows him photos of her son.

The video warns: “It may not just be friends and family reading your status updates.”

In another clip, two sailors head for a night on the town after telling friends they have just disembarked their ship.

One posts on Twitter that they will be going to a local club.

Once inside, she tells her Facebook friends of her location using the Foursquare app. Moments later she is seen dancing with the same camouflaged figure as he waves an AK-47 above his head in time with the music.

The clips have drawn parallels with Britain’s “Careless talk costs lives” propaganda campaign from the Second World War, in which Fougasse cartoons showed Britons talking as Hitler or Goebbels listened in.

The MoD said in a blog to accompany the videos: “It might only take one careless comment, or posting a picture without checking what’s in the background to put friends and colleagues at risk.”