The Berlin security services, which are responsible, among other things, for politically motivated crimes, have taken over the investigation into the sabotage that occurred last Saturday on the country's northern railway lines.

The train operator Deutsche Bahn (DB) then reported that the intentional cutting of its communication cables at two locations led to a temporary stoppage of all lines. Specifically, fiber optic cables in the Berlin district of Hohenschönhausen and the city of Herne in the western state of North Rhine-Westphalia were damaged simultaneously.

A police spokeswoman said, however, that it is not yet clear whether the damage to the lines was politically motivated, and that officers are investigating all possibilities.

The rail operator's reservation system also failed as a result of the damage, so all long-distance and some regional trains were suspended, leaving countless travelers stranded at stations.

"Cables that are essential for train traffic were deliberately and intentionally cut," said German Transport Minister Volker Wissing.

In this context, a representative of the police union on Sunday called for the surveillance system to be expanded.

"In the case of railroads, this kind of sabotage is always possible because cable lines are often also on open tracks and these are not fully monitored," Andreas Rosskopf, head of the union's Federal Police and Customs division, told the RND media network.

"We therefore need modern surveillance structures on the railroad, i.e. drones and sensor technology in the cable shafts, as well as a reinforcement of the railroad's own security personnel," Rosskopf explained.

With regard to Saturday's sabotage, he added that, "due to the structured planning, it can be assumed that these are possibly terrorist-type operations on the part of the perpetrators."