Three days after a fatal blaze razed a Shanghai apartment block, the question on the lips of many residents is how the building had effectively been lined with firelighters - on government orders - and just how many other homes are at risk of a similar fate.
The 12-year-old, 28-storey building was rapidly engulfed in flames on Monday afternoon, killing at least 53 people and putting scores in hospital.
It was being retrofitted with exterior insulation panels in a pilot energy conservation scheme by the local government. But the flammable polyurethane foam has been identified as a major contributory factor behind the scale of the disaster.
Two identical blocks next to the one that went up in smoke remained wrapped in scaffolding and green plastic mesh yesterday afternoon. Through gaps in the scaffolding, it was possible to see insulation materials had been fitted to sizeable areas of the walls. Although much of the foam looked to have been plastered over with cement, it was still visible in wide gaps where the work was unfinished.
There was almost no sign of such insulation remaining on the charred surface of the burnt building.
The two intact towers were still occupied yesterday, but police were guarding the compound's gates, and residents declined to be interviewed.