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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Kerrie brings you Saturday night's forecast
Sunderland suffer back-to-back relegations after last-gasp defeat to Burton Albion at the Stadium of Light
Dry, warm and sunny with sea breezes. Isolated heavy showers by evening and overnight