The Coroner, Ian Arrow, recorded a narrative verdict, concluding that Alan Levers had died during an attempted armed robbery.
He said the cause of death was a combination of factors as a result of his chest being compressed, wearing a gas mask with the respirator pressed against the floor, and all this was exacerbated by the level of alcohol he'd consumed.
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A teenage boy is also in hospital. Police believe both had suffered adverse reactions to an unknown substance.
Sunshine all day tomorrow and warm week ahead
Lovely and warm with highs of 23 and 24 degrees. Hottest on Wednesday.