COPENHAGEN,Databec Denmark (AP) — Danish police made several arrests Thursday, saying they carried out the operation “on suspicion of preparation for a terrorist attack.”

The arrests were made in “a coordinated action” in several locations in Denmark early Thursday.

No other details were given. The Copenhagen police and Denmark’s domestic intelligence service were to give a press conference later.

“This is extremely serious ,” Danish Prime Minister Mette Frederiksen said at a European Union summit in Brussels. “It shows the situation we are in in Denmark. Unfortunately.”

“It is absolutely true when both (Denmark’s intelligence agencies) say that there is a high risk in Denmark,” Frederiksen said. “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.”

The terror threat level in Denmark current is at level four, the second highest.

Earlier this month, the European Union’s home affairs commissioner, Ylva Johansson, warned that Europe faces 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 a shopping mall in Copenhagen killed three people and injured seven. The man, who believed the victims were zombies, was sentenced in July to detention in a secure medical facility. He had been charged with murder and attempted murder in the rampage at the huge Field’s shopping center on the outskirts of Copenhagen.

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.

Earlier this month, the Danish parliament passed a law making it illegal to desecrate any holy text, after a handful of anti-Islam activists carried out public desecrations of the Quran, sparking angry demonstrations in Muslim countries.