Multiple emergency services attended what firefighters called a "suspected hazardous materials" incident in Haywards Heath on Monday evening (7 August).
West Sussex Fire and Rescue Service, Sussex Police and SECAmb crews were called to Cedar Way at 4.49pm.
They were answering reports of a "chemical" smell within a property in the street.
Along with fire engines, a detection, identification and monitoring vehicle from Surrey Fire and Rescue Service also attended.
Firefighters said that several buildings were evacuated as a safety precaution, as investigations continued.
It was believed that any hazard was confined to a single address but, for a time, all nearby residents were advised to stay indoors, and keep windows and doors closed.
Several tests were carried out, firefighters said, and no hazardous materials were discovered.
The gas supply was isolated, and the gas network provider SGN were requested to carry out further tests.
By 10pm, crews said their presence had been scaled back, with the last crew leaving shortly after 11pm.
This was the scene outside Cedar Way (cinematography © Eddie Mitchell)
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