London: In an anti-terrorism operation spanning across four cities, Britain on February 6 arrested six men and a woman.

The arrests in London, Glasgow, Edinburgh and Manchester are being linked to an operation in December in which seven North African men were detained.

Lothian and Borders police made the arrests under the Terrorism Act 2000.

Two men were arrested in the Scottish capital Edinburgh, one man in Greater Manchester, a man and woman in Glasgow and two men in London, police said, adding premises where the arrests were made are being searched and "no dangerous" substance have been found so far.

Britain has been on heightened alert since the discovery of traces of the deadly ricin poison in a London apartment last month, following which anti-terrorist police made a string of arrests.

Deputy chief constable Tom Wood, of Lothian and Border Police, said "no dangerous substances" had been discovered in connection with the latest raids.

"This was a carefully co-ordinated operation which was executed successfully," he told BBC.

A police spokesman at the scene in Glasgow said he expected a search to last for around two days.

PTI