A road was closed while firefighters used specialist equipment to identify a potentially hazardous substance, which was sprayed a person by two teenagers on mopeds.

Essex County Fire and Rescue Service was called to Brook Street, Brentwood, at around 11.45am, after reports a member of the public was sprayed with the unknown substance.

Police had requested support from ECFRS’s detection identification monitoring (DIM) vehicle, which is used to identify hazardous substances.

By 2.30pm ECFRS’s incident commander confirmed that the substance had been analysed and was not harmful.

“As a precautionary measure the casualty was decontaminated, which involved removing them from the scene, removing their clothing and ensuring no substance was left on them,” An EXCFR spokesman said. “They were then left in the care of the ambulance service.”

Essex Police said the unknown substance was initially believed to be hazardous.

“The man was sprayed with what has been described as a powder on Brook Street, Brentwood by two teenagers on mopeds, who then rode towards the town centre,” a police spokesman added,

“A number of precautionary measures are being taken, including the closure of the Nagg’s Head Lane junction of Brook Street and where Brook Street meets Mascalls Lane.

“No injuries have been reported and we do not believe that there is any risk to the public at this time.”

Anyone with information about this incident is asked to call 101 quoting incident number 460 of 15/09.