Shock is giving way to anger in Hong Kong after a massive fire ripped through a densely populated subsidised housing estate on Wednesday, killing at least 128 people and critically injuring dozens.

Authorities say substandard mesh and plastic sheets on the buildings' windows may have spread the blaze, which raged for more than a day.

Firefighting operations have now ended, with dozens of residents still unaccounted for.

Questions are mounting as to how the fire at Wang Fuk Court spread so rapidly and who is responsible, with many calling it a man-made disaster.

Three people in charge of renovating the blocks are under arrest for manslaughter, and authorities have launched a corruption inquiry.

A post that has gone viral on social media in the wake of the blaze reads: It's not an accident.

Several residents have revealed in interviews that the fire alarm did not sound when the fire broke out.

Kiko Ma, who owns an apartment at Wang Fuk Court, says the alarms had been turned off amid renovation works, as construction workers regularly used fire escapes to get in and out of the building.

Ms Ma lives in Canada with her family, but visits the Hong Kong apartment several times a year.

This was preventable... A lot of people did not do their duties, the 33-year-old tells the BBC, claiming that the renovation firm used poor quality, flammable materials.

Residents often saw construction workers smoking and found cigarette butts along their window ledges, she adds.

People kept asking what would happen if there was a fire. Everyone was very worried about this.

This is Hong Kong's deadliest fire in at least 63 years - surpassing the toll of the August 1962 inferno in Sham Shui Po, which killed 44 people.

Built in the 1980s, Wang Fuk Court in Hong Kong's north-eastern Tai Po district comprises eight 31-storey buildings, seven of which went up in flames. The complex was home to about 4,600 people, nearly 40% of whom were 65 or older.

While police are investigating whether materials used during renovations met fire safety standards, some experts believe the bamboo scaffolding connecting the apartment blocks helped fuel the inferno.

Hong Kong authorities have ordered inspections of all housing estates undergoing major repairs to ensure safety compliance.