A huge police presence, including a dog unit and armed officers, has been seen at a property in Norwich city centre.

An eyewitness described four police cars and an armed police van outside in King Street at around 6.20pm today (Tuesday, August 15).

Norwich Evening News: A dog unit seen in King Street today (Tuesday, August 15)A dog unit seen in King Street today (Tuesday, August 15) (Image: George Thompson)

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There have been reports that the police used a drone and a dog unit during the investigation.

The reason for the investigation is not yet known at this time.

A spokesman for Norfolk Police has been contacted for comment.