Written by Jeff Stone

Germany’s federal police agency said Monday it has questioned suspects and searched property as part of its investigation into the data breach that led to the publication of hundreds of lawmakers’ personal information.

The Federal Criminal Police Office (BKA) said in a Facebook post that officials have been active in the town of Heilbronn, in southern Germany, in the hunt for information about the publication last week of phone numbers, addresses and other data about German officials and journalists. The announcement followed tweets from Jan Schürlein, a German IT developer who announced that authorities had spent four hours on Sunday looking through his home.

Da es überall im Fernsehen & den Medien zu sehen ist, ja dass BKA hat gestern in einer mehrstündigen Razzia meine Wohnräume durchsucht. Ich möchte ganz klar darauf hinweisen, dass ich ausschließlich als Zeuge geführt werde. Das BKA bat um öffentliche Zurückhaltung. — Jan Schürlein (@Janomine) January 7, 2019

Schürlein, 19, said he is being treated as a “witness” in the matter. In a Jan. 4 tweet, he published a screenshot of an internet chat with “@_0rbit,” one of the Twitter accounts that helped distribute the stolen information. In other messages, Schürlein said the hacker claimed responsibility for the breach and announced he planned to destroy his computer.

German authorities said Friday they were investigating the breach, which exposed information about Chancellor Angela Merkel and every party represented in the Bundestag, Germany’s parliament, except the fair-right Alternative for Germany. Authorities sought help from the U.S. National Security Agency and the Irish Data Protection Commissioner in cleaning up from the breach.

Horst Seehofer, Germany’s interior minister, told Sueddeutsche Zeitung he would tell the public “everything I know” about the incident after meeting with heads of the BKA and Germany’s cyberdefense agency, the BSI. The interior committee of the Bundestag is scheduled to meet in a special session Thursday to examine the breach, which one government agency initially blamed on Russian government hackers.

Data published following the breach appears to be from a mix of public and private sources, CyberScoop has reported. Some of the information is years old.