Detectives making inquiries into the sending of four toxic packages to prominent individuals including Cherie Blair and the Culture Secretary, Tessa Jowell, warned yesterday that more could still be in the postal system.
Politicians were told to be on their guard after extreme Scottish nationalists claimed they sent 16 of the packages last week. The warning came as Ms Jowell was confirmed as the latest politician to receive one of the packages, which contain a 10ml bottle of caustic soda disguised as a free sample of aromatherapy oil.
The first padded envelope, which was sent to Mrs Blair at Downing Street, was intercepted on Friday by security staff screening Number 10's mail at a separate site. The letter addressed to Mrs Blair was postmarked at the Glasgow mail centre on 25 February.
A leaflet accompanying the bottles, labelled eucalyptus oil, advised users to rub the substance into their hands and face. Caustic soda, also called sodium hydroxide, can cause blindness and severe burns.
Anti-terrorist officers were alerted by an anonymous call from a man claiming to represent the Scottish National Liberation Army, a fringe group linked with attacks on English targets since the 1980s.
A Scotland Yard spokesman said yesterday: "Given the nature of the postal service, there is a possibility that these items are still in the post or are sitting waiting to be opened in offices today.
"We have to take seriously the claim that a total of 16 of these packages were sent. If they are used in the manner that their sender intended, they would cause serious injury."
Detectives were understood to be liaising with their Gardai counterparts in Dublin last night about questioning Adam Busby, a founding member of the SNLA, over the warning call, which was made to the News of the World newspaper's Glasgow office.
Mr Busby, 53, a Glaswegian who served in the British Army and who lives in Dublin, says he is only involved with political activities to "halt and reverse mass English immigration to Scotland". But in 1997 he was jailed for two years for sending threatening letters to a Scottish newspaper and news agency. A Gardai source said yesterday: "An investigation is ongoing. We cannot comment further."
One of the packages was received on Friday by Margaret Ashcroft, an assistant of the English-born Liberal Democrat MSP Mike Rumbles, at her home in Banchory, Aberdeenshire. She was alerted before using the sample. The other letters, including the one sent to Ms Jowell at the Department of Culture, Media and Sport, are believed to have been received on about the same date but discarded after being opened.
The Yard refused to confirm reports that either the Labour MP Gwyneth Dunwoody or the Speaker of the House of Commons, Michael Martin, MP for Glasgow Springburn, received the fourth package.Reuse content