Police sealed off three streets in central London on Monday as they investigated a suspected chemical terror attack that turned out to be a Thai chef brewing up a particularly pungent burnt chilli sauce.

The three hour lockdown in Soho saw a Hazardous Area Response Team Unit and firefighters wearing breathing apparatus engaging in a 24 style hunt for the source of a cloud of acrid smoke, The Times reports.

Further analysis of the suspect substances, together with intelligence gleaned from the chef brewing up the fiery mixture, revealed they were in the process of being turned into a batch of Nam Prik Pao. The potent mixture may well cause burns and discomfort if abused, but is usually deployed with nothing more lethal than a bowl of prawn crackers and a bottle of cold beer.

A Scotland Yard spokesman told PA: "The street was closed off for three hours while we were trying to discover the source of the odour."

It's not the first time innocent cooking materials have morphed into potential bio-terror attacks. Just last month, police in New Haven Connecticut came down hard on a running club that used a trail of flour to mark a trail. They, understandably, assumed the baking ingredient could well have been anthrax. ®

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