A man is in hospital with serious injuries after setting himself on fire outside the Oslo courthouse where Anders Behring Breivik is standing trial for mass murder and terrorism.

Police say the man was seen pouring liquid over himself before igniting the liquid and trying to gain access to the court building.

He was stopped by security officials when he reached the temporary security tent set up to scan everyone entering the building during the 10-week trial.

A video posted on the website of the daily newspaper VG showed a man running towards the tent with his black hat on fire, shouting after dousing himself with liquid from a bottle. He is wrestled to the ground by armed security officers who stamped out the flames.

Kjell Kverme from Oslo police said the man had been taken to hospital with serious injuries to his stomach and chest.

Kverme said the man was believed to be Norwegian.