Members of the public were told to avoid a road in Norwich after a man was found acting 'suspiciously' in the area.
Officers were called at 9.08am to reports of the incident in Bluebell Road, in which a man was reported to be acting suspiciously and making threats.
Specialist officers were sent to the scene and a man in his 20s was arrested. He has been taken to Wymondham Police Investigation Centre where he will be questioned later today.
The road was closed as a precaution while police conducted a search of the area, but it reopened at around 12.30pm.
Officers are also conducting a search of an address in Earlham Road in connection with the incident.
City Academy in Bluebell Road, which has around 660 students, said in a post on Facebook that it was aware of the incident and that 'all students, staff and visitors are safe'.
It added: 'We are following police advice to stay in the building.'
Superintendent Dave Buckley said: 'Threats such as this are taken extremely seriously and whilst we do not believe there is an immediate risk to the public at this time, we are carrying out a search of the area as a precaution and to ensure the public's safety.
'We would advise people to avoid the area at this time.'
Superintendent for Norwich, Terry Lordan, added: 'We're in the early stages of investigating this incident.
'Threats such as this are taken extremely seriously; therefore steps were taken to close the road in the interests of public safety.
'I'd like to thank local residents and motorists for their patience and understanding whilst we carried out initial enquiries at the scene this morning.'
A police van was stopping vehicles entering Bluebell Road from the other roads off the Fiveways roundabout – including Gipsy Lane, Earlham Green Lane and Earlham Road – during the temporary road closure.
A police dog unit car was let in under the police cordon just before midday, while there was also a police car parked about half-way down Bluebell Road.
An 86-year-old woman, who lives near to the scene but did not want to be named, said she had not heard 'a thing' but was shocked to discover what had happened.
She said: 'It's horrible actually.
'I've got double glazing and we don't even hear the traffic.
'The dog has been out this morning but didn't hear her bark.'
Some people stopped to look at what was going on. One man, who did not want to be named, saw the police there earlier this morning but did not know why they were there.
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