It was the security police PST who, with the support of the Aliens Act, decided on the arrest, which happened just before 11 o'clock on Saturday, writes Norwegian NRK. The arrested man is American right-wing extremist Greg Johnson, which both NRK and VG have confirmed.

Johnson was present in Oslo to lecture at the right-wing conference Scandza forum. According to the police, the arrangement was legal.

Have defended terrorist acts

Martin Bernsen, press officer for PST, tells NRK that it is Johnson's political statements that underlie the decision. The American has previously, among other things, defended Anders Behring Breivik's terrorist act 2011.

- He can play an obvious radicalization role. He will be dispatched from Norway as soon as possible, says Bernsen.

Police forces on site

In a statement from Johnson, which should have been sent to NRK, Johnson denies, among other things, that he has supported the use of force as a political tool.

Large police forces are present at the conference due to protests against it.

- Several demonstrations have been announced in Oslo today. We believe that we have enough people to handle them, ”Brian Skotnes, intervention manager, tells NRK.