British PM's ex-media advisor arrested for perjury

Coulson, 44, was detained at his London home early today morning and was taken to Glasgow.

He has been arrested on suspicion of committing perjury at the 2010 trial of Tommy Sheridan, who was a member of the Scottish parliament.

Coulson, former editor of the media baron Rupert Murdoch's now defunct News of the World from 2003 to 2007, resigned as Cameron's director of communications in January 2011.

His appointment as the prime minister's director of communications has often embarrassed Cameron in the wake of the phone-hacking scandal.

A police spokeswoman said: "Officers from Strathclyde police's operation Rubicon team detained a 44-year-old man in London this morning under section 14 of the Criminal Procedure Scotland act 1995 on suspicion of committing perjury before the high court in Glasgow".

Coulson was the editor of the News of the World in 2006 when Sheridan won a defamation suit and 200,000 pounds in damages.

In 2007 he was charged with perjury, and in December 2010 he was convicted of perjury.

He was later sentenced to three years imprisonment.

After the phone-hacking controversy at the News of the World, the Crown Office has been ordered to reassess the Sheridan case.

Sheridan was released from prison on January 30, 2012, one year into his sentence.