A top police official has said information from a hacking attack on Germany's parliament may be used to try to influence the country's election.
Holger Muench, the head of Germany's Federal Criminal Police Office, did not say who was suspected of carrying out the attack, but warned it had led to a "significant drain of data".
The offices of at least 10 Bundestag MPs were attacked last month, the German news agency dpa reported.
The Bundestag was previously attacked in the summer of 2015, forcing several networks and servers to be taken offline for days.
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After an investigation, Germany's domestic intelligence agency (BfV) accused a hacker group working for the Russian state of carrying out that attack and others on state computer systems.
The 2015 attack involved attempts to install software that would have given the attackers permanent access to computers used by Bundestag staff and MPs.
Other attacks focused on stealing data about critical infrastructure such as power plants.
The BfV pinned the blame on the Sofacy/APT hacker group, which it said has been targeting Germany for more than a decade. Experts believe it is linked to the Russian state.
Russia has repeatedly denied responsibility for such cyberattacks.
German authorities have repeatedly expressed fears that foreign countries could try to influence the outcome of the elections by releasing hacked information during the campaign.
In January, the three main US intelligence agencies concluded that Russian president Vladimir Putin had ordered a campaign of hacking and other covert operations to influence last year's presidential election in favour of Donald Trump.
In France, Emmanuel Macron's campaign has accused Russia of hacking and spreading fake news in an effort to discredit the presidential frontrunner.