Copenhagen: Danish police said they had arrested four people on Thursday suspected of having been recruited by Islamic State (IS) to commit terrorist violence, and two others of breaking Danish weapons law.
Police said in a statement the four had been indicted for "having violated the penal code ... by allowing themselves to be recruited by IS in Syria to commit terrorist acts".
Later on Thursday police arrested two people they believe could be linked to ammunition and weapons found during a search carried out in connection with the earlier detention of the four.
The two will be indicted for breaking Danish weapons law, Copenhagen Police said in a statement.
Neighbouring Sweden on Thursday charged a 20-year-old man with terrorism for allegedly building a suicide bomb with the intent of staging an attack in Sweden.
The Danish arrests were part of a joint effort by police and the intelligence service PET to combat the enlisting of people by terrorist groups in war-torn areas of Syria and northern Iraq, police said.
The police would not provide more details on the identities of the six, or the charges against them. They will appear before a judge for preliminary hearings on Friday.
The prosecution had requested that Friday`s hearing for the four suspected IS recruits be closed to the public, police said.
More than 125 people are believed to have joined IS after going to Syria and Iraq from Denmark, PET said in October, adding that at least 27 had died there.
"We know that people who have fought for IS in Syria or Iraq may pose a specific security threat against Denmark," Justice Minister Soren Pind said in statement shortly after the arrests.
Only one person, a 23-year-old, has previously been charged under the same section of the Danish penal code with being recruited for terrorist acts. He was charged in December and his trial is expected to begin in May.
Danish authorities have been on high alert since two people were killed in shooting attacks at a free speech event and a synagogue in Copenhagen in February last year.
Islamic State claimed responsibility for suicide bomb attacks that killed 32 people in Brussels last month and attacks in Paris in November that killed 130 people.