We accept that the risk from a test involving boxes of micro-organisms which were driven around Swindon's

streets was probably small.

But we believe it's unacceptable that even one person might have been exposed to danger by the 1960s experiment which was designed to show how fast organisms would decay if they were used as a biological weapon in a Soviet attack.

Hopefully the dangers which were faced by the West during the Cold War are now a never-to-be-repeated part of history.

The story which is revealed in the report which we carry today will inevitably strike a chill in the hearts of countless people living in Wiltshire, home of the Porton Down chemical and biological warfare establishment.

The questions which need answering are: How many more of these secret experiments have taken place? And are they still being conducted?

After the revelations in Rob Evans' book, ordinary people might well wonder if they are still being treated as guinea pigs for a scary succession of secret manoeuvres which would do credit to a Len Deighton novel.

How many anonymous-looking lorries have trundled over our roads carrying test tubes with potentially toxic and even lethal contents?

The time for secrecy is over. It should not be left to the authors of books such as Gassed to tell us the truth.