Germany's BKA investigative police force said on Monday that it has questioned witnesses and searched properties as part of an investigation into a massive data breach affecting hundreds of German politicians.

A BKA statement posted to the office's Facebook page also included the town of Heilbronn by name. This followed numerous media reports and comments from a 19-year-old IT worker in Heilbronn, who said that investigators had contacted him.

BKA officers on Sunday searched a teenager's living quarters and household garbage and confiscated technical equipment at his residence in Heilbronn.

The young man, identified as Jan S., told the ARD show Kontraste that he had been questioned "for several hours" by police. He is being treated as a witness in the case. He says that he knows the hacker known as "Orbit," but that it is not him.

Read more: German cyber defense body defends itself over massive breach

The BKA also said it had begun to inform those affected by the hack, estimated to be roughly 1,000 politicians and celebrities, including German Chancellor Angela Merkel and President Frank-Walter Steinmeier.

Longtime correspondence

The young man has also been sharing some information on the case on his own Twitter account, acknowledging that he had been in contact with the hacker responsible for the data theft. According to him, the hacker contacted him shortly after the hacked data was published online, announcing plans to destroy his computer.

On Sunday evening, Jan S. posted a screenshot of an email from "0rbit," the presumed hacker, saying he was going to destroy his technical equipment. The 19-year-old went on to say that the hacker deleted his account with the Telegram messenger service, which the two had used for years to have encrypted conversations. 

The teenager had been suspected of being "0rbit" himself, a claim he has denied.

On Friday, Germany's Federal Office for IT Safety (BSI) revealed it was investigating the leaking of data about several politicians published on Twitter. The data included mobile phone numbers, contact info, and credit card details. 

German Interior Minister Horst Seehofer was to meet with the BKA and the BSI later on Monday, not least to discuss contradictory information from the BSI on precisely when it became aware of the case, with an early warning in December mistakenly written off as a one-off.

dv/msh (AFP, dpa)

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