Personal data and documents from hundreds of German politicians and public figures including Chancellor Angela Merkel have been published online in what appears to be one of Germany's most far-reaching data breaches.
A preliminary analysis showed the data had been obtained through "wrongful use of log-in information for cloud services, email accounts or social networks", Interior Minister Horst Seehofer said in a statement late on Friday.
He said there was no evidence that the computer systems of the German lower house of parliament or the government had been compromised, but provided no further details.
The ministry said it remained unclear if the breach, which triggered an emergency meeting of the BSI national cyber defense agency, was the result of a hack or a leak.
Authorities were investigating all possibilities, including espionage, according to one government source, who said it was unlikely that any single person could have compiled the massive amounts of data that had been released.
The public broadcaster RBB, which broke the story, said the data, published on a Twitter account, included addresses, personal letters and copies of identity cards. It said the identity of the perpetrators and their motive were not known.
The twitter account, which existed for four years and has now been deleted, first began releasing data in December in an electronic "Advent calendar". The extent of the data leaks first became apparent late on Thursday evening, sources said.
German media said a fax number and two email addresses used by Merkel had been published but the government said it appeared no sensitive material from her office had been released.
The hacked material included private chats by Greens leader Robert Habeck with family members and the identity cards of his children, a source familiar with the matter said.