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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Thousands of primary school pupils in the North East are expected to be absent today, as parents pull them out to protest against SATs.
Kerrie Gosney brings you Monday night's forecast
North East parents are most likely to raid their children's piggy banks to pay for things such as parking, takeaways and the tooth fairy.