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What's causing London's freak sidewalk explosions?

London's spate of exploding sidewalks, which have thrown fireballs and smoke into the capital's streets, are due to electricity cables being corroded by wet weather, a boss of one of the cable companies has admitted.

Basil Scarsella, Chief Executive Officer of UK Power Networks, told councillors for Westminster, a district in central London, that heavy rainfall was "more important" than aging infrastructure when it came the integrity of London's electricity cables .

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Sean Gallup | Getty Images

Yet some members of the local council Scrutiny Committee remained unconvinced, saying that the last two summers saw especially dry weather.

This year there have been 64 reported explosions, compared to just 51 in the whole of last year, according to the Health and Safety Committee.

As part of its measures to stem the sidewalk eruptions, UK Power Networks, which maintains electricity cables and lines across London and the South-east, inspects junction boxes in central London annually.

The company is also instituting interim measures such as specially designed blankets that compress oxygen levels around link boxes and using sand to stop fires inside chambers.

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Long-term plans including inspecting and replacing all of the aging underground electric network, and the company is in ongoing talks with regular Ofgem, for financial backing.

Regardless, ending explosions completely is "impossible", Scarsella said.

New Yorkers also suffered pavement explosions earlier this year, according to the New York Post.

Residents of an Upper East Side block were rocked by three separate explosions, after snow salt wore away underground electrical wire coatings.

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