Figures obtained by ITV Anglia show hundreds of gas appliances have been worked on by unregistered engineers here in the East of England.
Nearly 250 jobs were carried out by unqualified engineers over the past two and a half years.
Nearly one in five of those were so dangerous the appliances had to be disconnected immediately.
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Risk of heavy rain overnight and later Sunday.
Dry for much of the day. Some rain this evening.
It will be a fine start to the Bank Holiday weekend but there's a risk of heavy rain in some places by Sunday.