Six people have been arrested after police swooped on an area of Ipswich – but officers are still not saying what the incident involves.
Armed police were called to the scene as one of the town's busiest roads was closed this morning.
Norwich Road remains cordoned off in both directions near the junctions with Cumberland Street and Bramford Road.
Police have confirmed that six people have been arrested in connection with the incident and have been taken into custody.
They have not said what the people have been arrested on suspicion of and say they are carrying out inquiries to try to establish the circumstances.
Eye-witnesses said there were ambulances and dog handlers at the scene, as well several police cars and vans.
People in shops in the cordoned-off section of Norwich Road were instructed by police to either stay inside or leave out the back.
Most of the investigation taking place appeared to be happening near Cumberland Street.
Attention was focussed on a house in Cumberland Street, not far from the junction with Ann Street.
Police also sealed off Surrey Road, off London Road, but this has now been reopened and officers have left the scene.
A police spokesman said: "Six people have been arrested in connection with the incident and have been taken into custody.
"Ambulance crews also attended the scene.
"Any witnesses or anyone with information should contact Suffolk police, quoting CAD reference 101 of today, Saturday 23 November."
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