Nato troops have been persuaded to abandon their posts and reveal sensitive details about military manoeuvres in a clandestine social media operation launched by their own side.

More than 150 soldiers were snared in the so-called "catfishing" trap which used Facebook and Instagram to manipulate them.

A secret "'red team" based at Nato's Stratcom Centre of Excellence in Latvia targeted the unwitting troops as they took part in a scheduled military exercise "in an Allied country".

While it remained unclear on Saturday night whether any British servicemen or women were targeted in the operation, British military and cyber experts warned that the report was a worrying development.

Stratcom’s report did not reveal which of the 29 Nato countries was subject to the test. However, the report has been presented to Congress in Washington.

It detailed how operatives set up fake social media pages, luring soldiers into closed Facebook groups, where fake accounts then asked them sensitive questions about the military exercise they were involved with.