Bricks dug out from pavements are seen left on a chair after protesters clashed with riot police at Mong Kok district in Hong Kong, China, Feb 9, 2016.[Photo/Agencies]

One week after the riot in Hong Kong, the special administrative region is still trying to come to grips with what happened in the Mongkok streets.

Many residents are wondering why their home city, which used to be ranked the safest in the country, has turned into something they no longer recognize, after some 90 law enforcement officers were injured by a brick-hurling and fire-setting mob.

The riot has dealt a blow to the city's law and order and presented a grave challenge to the authority of the government and police. It has also rubbed salt on the wound of an already declining tourism industry and tarnished the reputation of Hong Kong.

The SAR government will certainly launch a thorough investigation into the cause of this ugly event and determine what should be done to prevent any recurrence.

The main culprits are the lawless rioters who gathered to resist the rightful eviction of illegal hawkers in Mongkok on Monday night. But that violence was only the latest in a string of events that send a clear signal that more escalated violence can be expected.

Behind the violence are forces determined to work against the SAR and central governments. The pawns of these forces are young people frustrated by the city's faltering economy and brainwashed by anti-mainland and anti-establishment ideas.

To address the root cause of the riot, therefore, the SAR government must review the existing policies in the realms of education, employment and housing. The school curriculum, for instance, should be revamped, with national education introduced and civic education strengthened.

The opposition camp, which excused the riot by insisting it was provoked by the government, has lost its self-assumed "moral high ground". Any candidates in the upcoming elections supporting such violence will pay a heavy price as voters will tell them HK people do not condone it, whatever the justification.