Hong Kong's six disciplinary services on Sunday held a flag-raising ceremony to mark the 40th anniversary of the promulgation and implementation of the Chinese constitution.

The flags were then lowered to half-staff to mourn the passing of former president Jiang Zemin.

Speaking at the event, Secretary for Justice Paul Lam said disciplinary services are in the vanguard of protecting national security, adding officers are also responsible for helping people learn about the constitutional order and strengthening their national identity.

Lam said people should start learning and respecting the constitution from a young age, and should nurture the good qualities of safeguarding the rule of law and being law-abiding.

He said this is very important for the future development of Hong Kong and the nation.

Meanwhile, Financial Secretary Paul Chan also said comprehending the constitution and the Basic Law was key in the implementation of "One Country, Two Systems".

He made the remarks on his blog, where he said Hong Kong has the responsibility to make use of its unique advantages and contribute to the modernisation of China.

Chan pledged to make Hong Kong’s financial services “bigger and stronger”, so it can better support the SAR and the mainland’s economic growth.

He also said Hong Kong should take advantage of its One Country, Two Systems, the enormous mainland market, as well as its position within the Greater Bay, and boost its financial and other industries with innovative technology.