Some of the flats had metal gates in front of them, others had cloth over the front door window to prevent prying.

Lilian Heseltine, 69, has lived in the tower block in Tottenham, North London, for 30 years. “No way would I leave the door open, and I have never seen police patrolling inside the building,” she said.

“I’m not really happy here, but home is what you make of it and it is better than it was. I don’t want to move.”

The picture was similar at Stellar House, farther down the high road. A bored guard sat in reception monitoring his closed-circuit television screens and an entry phone had been installed to exclude non-residents. But it does not work, according to Sarah Elgar, 21.

“You can get in if you don’t live here,” she said. “I see people smoking crack in the corridors and on the stairs.

“I would never leave my door unlocked. Nobody that I know of does. The police don’t patrol the building. The only time you see them they run past looking for someone. I was born in this area and the crime has got worse.”

Laura Barrett, 38, a nurse whose motorbike was stolen recently, laughed at the suggestion that she would leave her door open or unlocked. “No way,” she said.

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