German police said it had not excluded political motives in the suspected sabotage of communication cables on Germany's rail network but that there was no sign of any involvement by a foreign state or terrorism.
A spokesperson for the Berlin criminal police bureau said on Sunday that it was still investigating the sabotage of radio communication cables in Berlin and Herne in North-Rhine Westphalia (NRW), which halted all rail traffic in northern Germany for around three hours on Saturday.
Germany's federal police has handed the case over to Berlin and NRW criminal police bureaus.
This is not the first time there have been attacks - often linked to leftwing extremists - on the communications system of state rail operator Deutsche Bahn, although it is the biggest one in recent years.
Fears have grown since the Russian invasion of Ukraine and attacks on the Nord Stream pipelines of targeted assaults on Germany's critical infrastructure.
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