Porton Down says Russian suggestions of link to the Salisbury attack are "frustrating".
The BBC's security correspondent Gordon Corera has spent a day in the military's chemicals headquarters in Wiltshire.
News, sport, weather and travel updates for the West of England.
Russia is behind the attempted murder of an ex-spy and his daughter in Salisbury, the PM believes.
Steve Cooper was in the the Mill pub in Salisbury where traces of a nerve agent have been found.
Joe Simmonds kicks a penalty five minutes from time to send Exeter 11 points clear at the top of the Premiership.
Millwall striker Harry Smith is receiving help for mental health and addiction issues, the Championship club says.
Wiltshire Gazette and Herald
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