David Cameron's former communications chief Andy Coulson has been charged over allegations he committed perjury during the trial of former MSP Tommy Sheridan.
The 44-year-old was detained for questioning at Govan police station in Glasgow – after being arrested in London – by officers from Strathclyde Police.
More than six hours later, the force confirmed he had been arrested and charged with perjury.
A report will be sent to the procurator fiscal which will decide if Coulson is to face court proceedings.
The former News of the World editor gave evidence at Sheridan's perjury trial at the High Court in Glasgow in December 2010, while he was employed by Downing Street as director of communications.
At the trial, he claimed he had no knowledge of illegal activities by reporters during the time that he was editor of the now-defunct newspaper.
He said: "I don't accept there was a culture of phone hacking at the News of the World."
Sheridan was ultimately jailed for three years in January last year after being found guilty of perjury during his 2006 defamation action against the News of the World.
He had been awarded £200,000 in damages after winning the civil case but a jury found him guilty of lying about the tabloid's claims that he was an adulterer who visited a swingers' club.
The former Scottish Socialist Party (SSP) leader was convicted of five out of six allegations in a single charge of perjury relating to his evidence during the civil action at the Court of Session in Edinburgh.
Sheridan was released from jail in January this year after serving one year of his sentence and vowed to continue the fight to clear his name.
Coulson was arrested last year in relation to Scotland Yard's long-running investigation into phone hacking at the newspaper.
He was held in July on suspicion of conspiring to intercept communications and corruption, and had his bail extended earlier this month.
Coulson resigned as editor in 2007 after the paper's former royal editor Clive Goodman and private investigator Glenn Mulcaire were jailed for phone hacking.
In May that year, he was unveiled as director of communications and planning with the Conservative Party.
He quit his role as Downing Street communications chief in January last year after admitting the News of the World phone-hacking row was making his job impossible.
Operation Rubicon detectives have been looking at whether certain witnesses lied to the court during Sheridan's trial as part of a "full" investigation into phone hacking in Scotland.
Officers detained Coulson in London yesterday morning before bringing him to Glasgow.
A Crown Office spokesman said there was no legal obligation for Coulson to stay in Scotland, and that he was free to return to his home in London.
He said no date had been set for any court appearance.