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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A 16-year-old boy accused of killing two people in Colchester has appeared in court today.
A fine and generally dry day with a light breeze and plenty of long sunny spells, though becoming cloudier through the afternoon.
Saturday will be the best day this weekend before rain on Sunday.