Emergency services and the military surrounded a council building in South Tyneside yesterday in what appeared to be a large-scale operation.
However, the dramatic sight of cordoned off areas and uniformed personnel standing guard at the old offices in Campbell Park Road, Hebburn, were nothing more than a training exercise.
The scenes sparked a flurry of conversations on social media as people were left wondering what was going on.
Police, ambulance and the military were involved in the exercise, which lasted for the best part of the day.
One passer-by said: “It looked quite surreal. The area was taped off and there were lots of people in uniform taking part in what looked like some kind of role play.”
A spokesman for Northumbria Police said: “We are aware of a training exercise in Hebburn and there has been no concern for the public.”