Germany has arrested two teenagers who were allegedly planning terrorist attacks on a synagogue and Christmas market to take revenge against “infidels”.

The German security services said they arrested a 15-year-old and a 16-year-old over the plot, which was supposedly due to take place on Dec 1. The arrests took place in North Rhine-Westphalia and Brandberg states respectively.

One of the teens reportedly declared a war on the West in an online video where he warned that an attack would occur at a specific place on Friday.

Very few details about the youths have been released, in order to protect their identities in accordance with German privacy laws.

Germany is facing a major terror threat, with the country’s domestic intelligence agency warning that the danger is “higher than it has been for a long time” in the wake of the Israel-Hamas war.

In a threat assessment, the head of the Federal Office for the Protection of the Constitution said Germany needed to be extremely vigilant about Islamist attacks in the near future.

“I have repeatedly emphasised that an Islamist attack can be carried out in Germany any day,” said Thomas Haldenwang.

He stressed that the war in Gaza had led to increased calls for violence across the “jihadist spectrum” and not just among Hamas supporters in Germany.

“This could lead to the radicalisation of perpetrators acting alone who attack ‘soft targets’ with simple means. The danger is real and higher than it has been for a long time,” he said.

German authorities have stepped up security at large events and in Jewish communities in light of the threats.

In December 2016, a truck was deliberately driven into a Christmas market at Breitscheidplatz in Berlin, killing 12 people and wounding dozens. Responsibility for the attack was later claimed by the Islamic State, which at that point was at the height of its influence in the Middle East.