Speaking to the Islington Gazzette, Umit Bakir, who works for a minicab company said:
I looked outside and I could see the fire coming up from underground. Then the fire brigade came and closed the road. My business was far enough away, but if I had been at Iceland I would have been a bit worried.
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Before the final declaration on Friday, the Conservative candidate looked set to lose the City Hall race to Labour's Sadiq Khan.
The Tooting MP has been the frontrunner in the counting process ahead of Tory challenger Zac Goldsmith.
It's not just London where elections have been taking place today. There were council elections taking place across the home counties.