A university library was evacuated and firefighters called after burning machinery triggered an alarm.
Norfolk Fire and Rescue Service confirmed they had sent six crews - from Wroxham, Hethersett, Sprowston, Carrow and two from Earlham - to the University of East Anglia library building just before 3.15pm on Thursday afternoon.
UEA Twitter accounts posted to say a fire alarm was sounding and that the building had been evacuated 'as a precaution'.
The service tweeted to say: 'We are currently attending an incident at the UEA in Norwich, please avoid the area further updates to follow.'
The university's estates team warned that there was limited access along Suffolk Road, at the back of the union shop and Barclays bank, as well as through to Chancellors Drive.
There were about 30 firefighters involved, with the aerial ladder platform used. On the fire and rescue service's incident log, it said crews used breathing apparatus, main jets and thermal imaging cameras.
Alan Nicholls, incident commander for Norfolk Fire and Rescue Service said: 'We were called to reports of a fire in the library, in the plant room, which is on the roof.
'There were reports of smoke and that had triggered the automatic smoke alarm. The building had already been evacuated on our arrival.
'Our units went in with breathing apparatus and we believe the smoke was caused by an overheated drive belt on a piece of machinery.
'Because of the high rise nature of the building, we needed a lot of resources, because we needed to pump water to the roof and we used the aerial ladder for observation.'
A spokesman for the University of East Anglia said: 'Precautionary measures were taken this afternoon to evacuate the UEA library after burning rubber was smelt. The fire service was also in attendance.
'The library has now re-opened after investigations found there was no fire.'
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