When university student Miles Kwan launched a petition demanding answers from Hong Kong authorities after one of the city's deadliest fires last week, he was arrested.

The ferocious blaze had ravaged a densely populated housing estate in the northern Tai Po district, killing at least 159 people and displacing thousands.

As public anger grew, the pro-Beijing authorities warned, repeatedly, against attempts to exploit the fire to endanger national security.

Kwan was reportedly arrested by Hong Kong national security police on suspicion of sedition. He is now on bail, according to local media.

Police told the BBC that it would handle any action taken in accordance with the law and the actual circumstances.

There was also a strong public reaction to the arrest. To some, the decision to arrest him was baffling. To others, it was simply Beijing's playbook, replicated. The Hong Kong government says that it's about trying to protect rule of law in a testing moment for the city.

Ronny Tong, a member of Hong Kong's Executive Council, disputed the suggestion that Hong Kongers are being suppressed. The government is trying to be prudent, he tells the BBC.

Regina Ip, another Hong Kong lawmaker, also defended the arrests. Authorities are being extra careful that public anger does not lead to a recurrence of the 2019 riots, she told the BBC's Newshour radio programme.

Among the questions in the petition and being asked by many Hong Kongers include how the blaze could have swept through the buildings so rapidly and whether any government officials should be held responsible.

Kwan's petition, which listed four demands - echoing the five demands, not one less slogan that rallied protesters in 2019 - gathered more than 10,000 signatures in less than a day before it was taken down.

Days later, the city's leader John Lee said Hong Kong would go all out to support victims and investigate the blaze. He announced a number of actions such as the convening of an independent committee to investigate the fire, a review of the building works system, and temporary accommodation and financial aid to victims.

In the past week, authorities have also arrested 15 people on suspicion of manslaughter and ordered the removal of mesh netting from all buildings undergoing renovations after investigators found that the one wrapped around the charred complex did not meet flame retardant standards.

China's national security office in Hong Kong swung into action swiftly after last week's disaster, warning that it would take action against anyone trying to instigate black terror - a phrase Beijing had used to describe the 2019 protests.

In a more strongly-worded statement this week, it vowed to punish hostile foreign forces... no matter how far away they may be.

Lee, Hong Kong's chief executive, said he would ensure justice is [served] to anyone who tries to sabotage relief efforts.

Asked at a news conference earlier this week why he deserves to keep his job following the fire, John Lee sidestepped the question and instead pledged to take to task anybody who dares to sabotage relief efforts.