The Norway mosque shooting is being probed as an act of terror and the man suspected of opening fire at a mosque has expressed right-wing sympathies online.

Superintendent Rune Skjold told reporters the suspect, described only as a Norwegian man in his 20s, has praised figures like Vidkun Quisling, the leader of Norway under Nazi occupation during World War II, reported CNN.

The suspect was allegedly inspired by by alleged white supremacist shooters in Christchurch, New Zealand and El Paso, Texas, say media reports.