Police have issued a drugs warning after four people were taken ill at a Halloween event in Leeds.
Officers were called to The Pavilion in Elland Road at about 12am on Sunday after ambulance staff reported concerns for two women and two men who had attended the event and were receiving emergency treatment for suspected Gamma Hydroxybutyrate (GHB) overdoses.
The women aged 30 and 31, and the men aged 21 and 25 were later released from hospital.
A 32-year-old man was arrested on suspicion of supplying controlled drugs and is currently in custody while enquiries continue.
Detective Inspector Jaz Khan, of Leeds District CID, said:
"We would urge anyone who has recently purchased this substance in the Leeds area to throw it away, as it is possible there may be a contaminated batch in circulation.