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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Dry, sunny and chilly
NHS workers have staged a four-hour strike in a row with the Government over pay.
A cold, frosty start. Then a fine and dry day in the Anglia region with plenty of sunshine. Winds will remain light.