Two people are fighting for their lives after multiple knife attacks have reportedly taken place in Norwegian city Sarpsborg.
One person is understood to have been arrested around 1.30am local time in relation to the alleged stabbings - said to have taken place at various addresses in the city, according to local media.
Three people are reported to have been attacked from 00.19am, with two in critical conditions and one having been stabbed in the arm.
One crime scene is understood to have been set up in a car park.
Local newspaper Sarpsborg Arbeiderblad has reportedly been told by the husband of one of the victims the perpetrator knocked on their door and entered their home before the attack.
The man told reporters he was watching TV when he heard the knock at the door and that the attacker had initially tried to stab him.
A photo of armed police in the southern city's centre appears on the SA website.
Police have told people to stay in doors but motivation for the attacks or whether more than one person was involved is unclear.
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