The Prime Minister's official spokesman said Ofgem has given "a very strong signal" that energy companies will not "get away with" bad practice after the it fined ScottishPower £8.5 million.
Asked if David Cameron was happy with the level of the fine, he replied:
Those must be, of course, decisions for the regulator but I think it does send a strong signal in response to bad practice that was being looked at here.
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Five people, including three children, have died after being electrocuted in a pool at a water park in Turkey, it has been reported.
Dan Evans, who is currently ranked third in the UK men's rankings and 50th in the world, said: "I made a mistake and I must face up to it."