Far-right extremists in Germany are joining forces with like-minded groups across Europe and even the United States as they prepare to carry out more attacks, the country's intelligence chief has warned.
Hans-Georg Maassen, the head of the Verfassungsschutz, said the agency had been forced to step up its efforts to foil plots by neo-Nazi and fascist groups following a surge in extremist violence in 2015.
"This is not just purely a German phenomenon," he told Reuters, "the Right-extremist scene is networking on a European level, and in some cases, with connections in the United States."
"We have seen in a series of cases that there are numerous people in the far-Right extremist scene who are ready to do anything and who have joined forces to create Right-wing terrorist cells."
He added: "We are trying to investigate these cells, if they exist, and to prevent any attacks."
Mr Maassen's remarks came after the Verfassungsschutz's annual report revealed that cases of far-Right violent acts in Germany had increased by 42 per cent to 1,408 in 2015.
The number of arson attacks on refugee centers has also surged to 75, compared to just five in the previous year.
It is feared that much of the violence is in reaction to the influx of more than one million migrants and refugees into Germany last year as part of Chancellor Angela Merkel's "open door" immigration policy.
Public support for far-Right political parties in Germany is at a record high, with the anti-Islam "Alternative for Deutschland" (Afd) group surging in the polls.
One recent study found that the Afd, which believes Islam is "incompatible" with German society, is now the country's third largest party.
The anti-immigrant movement Pegida has also risen to prominence in Germany, despite being accused by Sigmar Gabriel, the German vice-chancellor, of drawing on the "battle rhetoric" of the Nazi party.
Germany is reeling from a spate of violent terror attacks which took place earlier this year, several of which have been linked to far-Right extremism.
In July, a Munich teenager who was reportedly inspired by the far-Right Norwegian terrorist Anders Breivik gunned down 10 people and injured 36 others near a shopping centre.
Investigators found sheaths of Right-wing extremist material at the 18-year-old's home and said he was "clearly inspired" by Breivik's massacre of 77 people in 2011.
More recently, in October, a police officer was shot dead by a member of the "Reich Citizens," a group which refuses to believe in the fall of the German empire and does not recognise the modern German state.
The following week, a member of the same group was arrested on suspicion of an arson attack on a family of refugees.
In May, more than a thousand far-Right activists held a rally outside Berlin's main railway station protesting Mrs Merkel's refugee policy.
Many chanted slogans such as "No Islam and German soil" and "Merkel must go" while others donned T-shirts with messages such as "Rapefugees not welcome."
According to the Verfassungschutz, there are an estimated 11,800 violent far-Right extremists in Germany.