Tests on a mystery substance that left three Auckland paramedics needing hospital treatment yesterday have proven inconclusive.
St John Ambulance said the men suffered from nausea and dizziness after inhaling fumes while treating a man who had taken drugs at Westfield Manukau.
The man told fire crew members he was taking morphine before he was found in a toilet at the mall.
St John said the Fire Service carried out tests with a "sniffer machine" but the results were inconclusive.
A police spokesperson said no charges would be laid over the incident and police were no longer investigating the matter.
St John said the paramedics were overcome by fumes and complained of nausea.
The paramedics where taken to hospital but sent home soon after, while the man they were treating is in a stable condition.
It is not yet known what caused the fumes.