Hundreds of workers spilled on to city streets yesterday after at least six fire alarms were activated in the Dunedin central business district.
Emergency services said the false alarms - allegedly maliciously triggered - could have had disastrous consequences.
Dunedin Senior Station Officer Rob Torrance said the first alarm sounded at the Work and Income office in Cumberland St at 2.19pm.
Dunedin City Station responded to the first call.
Within 20 minutes, all eight available appliances - including Mosgiel, Ravensbourne and a ladder truck - had been called.
''It is a complete waste of resources,'' Mr Torrance said.
''That epitomises what we don't want to happen: all our appliances being involved over such a short time.''
Almost 30 firefighters attended the false alarms, including at Cadbury and Radio Otago House in Cumberland St, and Investment House, Otago House and Public Trust Building in Moray Pl.
Two fire appliances had been fighting a small fire in Brockville just before the alarms.
Roslyn Fire Station Officer Justin Wafer said he was attending to a ''smoked-logged'' house in Brockville when the crew were called to the ''frustrating and unwelcome'' alarms.
The evacuation of hundreds of workers would have been detrimental to the Dunedin economy, he said.
''There would have been a lot of business lost ... '' Mr Wafer said.
''Some of those buildings have hundreds of people in them and a lot of business carried out within.''
Otago Chamber of Commerce chief executive John Christie said he was listening to the 2014 Budget in the Public Trust Building when the building's alarm sounded.
About 200 staff had evacuated the building, he said.
The ''annoying'' business interruption was inconvenient and would have cost businesses money, he said.
''You are talking about firms on billable hours in some cases and that is lost productivity.''
Sergeant Reece Munro, of Dunedin, said a 32-year-old Dunedin man was due to appear in the Dunedin District Court today charged with knowingly giving, or causing to be given, any false alarm of fire.
Further charges were likely, Sgt Munro said.
''It's something we take quite seriously, given the impact it has on the community.''
