Croydon Council's headquarters were evacuated this morning after fire sprinklers malfunctioned.
Staff were herded out of the £140m Bernard Weatherill House, which opened two years ago, at about 8.30am.
It is understood the sprinklers on the building's second floor were triggered by electrical wiring, which had been exposed by part of the ceiling falling off.
A council worker, who did not want to be named, said: "It's supposed to be a spanking new building but it's falling apart.
"It will mean possibly damaged PCs, laptops and printers."
Staff returned to the building at about 10am, with employees on the second floor relocated to other desks.
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