Rebekah Wade, editor of the Sun, has been arrested for an alleged assault on her husband, the EastEnders actor Ross Kemp.
Ms Wade remains in custody at a police station in south London following a dispute at the couple's home in Battersea in the early hours of this morning.
A spokeswoman for Scotland Yard said: "At 4am this morning officers attended an address in south London regarding an alleged assault. A woman was arrested for alleged assault on a man and is now in custody at a police station in south London."
The Sun has been contacted by MediaGuardian.co.uk for a statement but had not returned calls by the time of publication.
News of Ms Wade's arrest will prove particularly embarrassing for the paper as Rupert Murdoch, the chairman and chief executive of Sun parent company News Corporation, is in London for tomorrow's BSkyB annual general meeting.
Ms Wade and Kemp, who became a household name playing hard man Grant Mitchell on the BBC soap, were married in a ceremony in Las Vegas in 2002.
The pair, who often dine at exclusive London restaurant The Ivy, have a coterie of famous friends including David Blunkett, the work and pensions secretary who resigned yesterday, and Guy Black, the Tories' press secretary and former director of the Press Complaints Commission, and his partner Mark Bolland, Prince Charles' former adviser.
Thirty-seven year-old Ms Wade made history in 2003 by becoming the first female editor of the Sun - the country's biggest selling daily paper with 10 million readers - and has used the paper to campaign against domestic violence.
She became the youngest editor in Fleet Street at News International sister title the News of the World where her tenure was characterised by the "naming and shaming" of known paedophiles following the murder of schoolgirl Sarah Payne.
It was only after attacks on innocent men wrongly targeted as paedophiles by vigilantes, the vilification of paediatricians mistaken for child-abusers, and riots in Portsmouth that Ms Wade reluctantly ended the campaign.
She built her reputation at the News of the World with a string of memorable scoops including the Prince Harry drugs scandal, Angus Deayton, and the Countess of Wessex sting at the hands of investigative editor Mahzer Mahmood.
In her debut editorial at the Sun Ms Wade fired off a warning shot over the bows of the government and before this year's general election threatened to switch the Sun's support to the Tories before caving in and backing Mr Blair.
She has disappointed many feminists by embracing the topless page three girl tradition when many had hoped she would ditch the page.
The paper suffered a blow in May when its star columnist, Richard Littlejohn, was poached by the Daily Mail on a salary believed to be worth up to £1m a year. A legal tussle over the signing was eventually settled out of court this month.
The feeling remains that Ms Wade has struggled to continue the success at the Sun, where it has been out-scooped by the Mirror and her former title.
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