Hong Kong authorities have arrested 13 people on suspicion of manslaughter in connection with a massive fire that killed at least 151 people and left more than 40 missing at the Wang Fuk Court estate in Tai Po, the city's deadliest blaze since 1948.
Investigators cited substandard green mesh netting and foam insulation used in renovations, materials that failed fire-retardant standards and were concealed from inspectors.
Malfunctioning fire alarms and flammable scaffolding coverings contributed to the rapid spread of the flames across seven towers last Wednesday.
Search teams in hazmat suits continue scouring the most damaged buildings, where some remains have been reduced to ash, with operations expected to last weeks.
More than 1,100 survivors have been relocated to temporary housing and another 680 placed in hostels and hotels.
The government has provided emergency payments of HK$10,000 per household and expedited replacement of lost identity documents.
Thousands of mourners have gathered at the site, while vigils are planned in Tokyo, London, and Taipei.
Amid public demands for accountability, national security police detained several individuals linked to petitions seeking an independent commission of inquiry.
Among those held were student Miles Kwan, former district councillor Kenneth Cheung Kam-hung, and a volunteer coordinating survivor aid, with charges including sedition and inciting discord.
A petition that collected over 10,000 signatures before removal called for transparency and examination of possible regulatory failures.
Beijing's national security office warned against exploiting the tragedy to incite unrest, vowing strict punishment for those attempting to "disrupt Hong Kong through disaster."
Amnesty International urged authorities to allow freedom of expression and conduct an impartial investigation rather than suppress legitimate questions.