Several police officers were called to a Norwich city centre restaurant.
Four cars and a van attended Spice Lounge in Wensum Street about 7.45pm on Friday evening (May 21).
Eye witnesses said the officers had "pulled up in a hurry" and spoke to staff.
Police have so far not given any more information but said the incident was over by 8.30pm.
Spice Lounge has been approached to comment.
A spokesman said: "We're too busy to talk."
More to come.
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