Police and paramedics were called to the property in Heaton Moor just before 5am on Sunday and initially three people were taken to hospital.
About an hour later - as a police investigation was beginning - more people who were at the party became ill and paramedics were called a second time.Three more casualties were taken to hospital.Of the six who had become ill, three were in a serious condition and had to be placed on ventilators.
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