Two men aged 23 were arrested on suspicion of being concerned in the supply of a controlled drug and have been bailed.
Six men aged 19 to 22 were taken to hospital overnight from a house at Ripon Gardens in Newcastle. One of the men is critically ill. Police believe the six had taken a hallucinogenic drug.
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Northumbria are appealing for help from the public to trace a wanted Gateshead man.
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