German prosecutors said Dutch national Nazih R was arrested in Rotterdam. Lebanon-born Abdelhamid Al A and Ibrahim El-R, as well as Egyptian national Mohamed B, were arrested in the German capital, they added.

The statement said all four have long-been members of Hamas – with ties to the leadership of the military branch.

Danish Prime Minister Mette Frederiksen spoke about the arrests to reporters at the European Union Summit in Brussels.

She said: “This is extremely serious…It is of course, completely unacceptable in relation to Israel and Gaza, that there is someone who takes a conflict somewhere else in the world into Danish society.”

In the Netherlands, broadcaster NOS reported that a 57-year-old Dutch man was arrested in Rotterdam based on a request from German authorities.

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Earlier this month, the European Union’s home affairs commissioner, Ylva Johansson, warned that Europe faced a “huge risk of terrorist attacks” over the Christmas holiday period due to the fallout from the war between Israel and the Palestinian militant group Hamas.

In July 2022, a gunman at the huge Field’s shopping center on the outskirts of Copenhagen killed three people and injured seven. The man, who believed the victims were zombies, was charged with murder and attempted murder and ultimately sentenced in July to detention in a secure medical facility.

In 2015, a 22-year-old Danish Muslim gunman killed two people and wounded five others at a free speech event and a synagogue in Copenhagen.

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