Police were called to the address in Ashington in the early hours of this morning, where they found the 20-year-old man with stab wound to the chest.
Three people have since been arrested on suspicion of wounding, and police are appealing for information about the incident.
The man is reported to be a in a critical but stable condition.
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Police in Newcastle have arrested 13 people as part of a campaign to tackle crime and disorder in the west end.
Kerrie Gosney brings you Sunday night's forecast for the Tyne Tees region
The remains of Hurricane Gonzalo will reach the UK on Monday night, bringing a period of strong winds and heavy rain to the UK.