Tonight's story in Westminster, reported by Iain Dale and many others, is that Shadow Immigration minister Damian Green has been arrested (not charged) for conspiracy to commit misconduct in public office.
The initial signs are that Cameron is standing by him and citing the public interest, which is going to make for an interesting and - perhaps - decisive beginning to a battle between the Tories and Labour for the hearts of the electorate.
On the face of it there is little that an immigration shadow could do in terms of bringing information into the public domain which could not be in the public interest. By contrast - the actions of Robert Peston and his (presumably Labour) sources recently have done massive damage to our banks and, on the face of it, contravene the rules by which the rest of us operate in public markets. That's before we even think about the massive amount of spin and innuendo generated by this Government and only possible because of their access to privileged information.
There is a real possibility that this is a politically motivated action, and if so, it marks a sinister day indeed for British Politics.