Unknown persons have committed several acts of arson on German railway installations Sunday night and Monday morning, bringing parts of the railway network to a halt, police said.
According to the German Federal Police, 14 arson attacks have been committed, two of which were successfully prevented. The perpetrators set fire to electrical lines along railways. No persons were injured, Xinhua news agency reported.
Rail passengers had to endure train delays or use alternative transportation. The German railway company, Deutsche Bahn, released several statements informing passengers of the delays caused by vandalism.
The areas affected were Berlin, Hamburg, Cologne, Dortmund, Leipzig and Bad Bevensen and Lower Saxony.
The cable fires were started with unconventional explosive and incendiary devices, according to the Federal Ministry of the Interior.
A letter of confession was found online on the open news web platform Indymedia and is under investigation, according to a Berlin police representative.
A security expert was quoted by the German press agency DPA as saying that a connection to left-wing extremism related to the upcoming G20 Summit was conceivable.
In 2011, left-wing extremists set fire to a cable bridge at a railway station in Berlin, crippling a large part of the local public transport.