The Norwegian police said as many as 30 Norwegian citizens who went to Syria to participate in hostilities there have been killed, while, Norwegian ABC Nyheter reported.
The paper quoted the Norwegian police as saying that about 100 Norwegians have left their country to Syria and joined the Daesh militant group, adding that another 30 Norwegians are still in Syria and their fate is unknown.
"We know very little about those who are currently in Syria," said Martin Berenson, Norwegian police senior adviser.
"There are also at least 20 children of the Norwegians who had left for Syria" he added.
The police reported the return of 40 Norwegians from Syria to their homeland, noting that all returnees are currently under observation, while some were put in prison.
There are no women among returning citizens.