HONG KONG - Commenting on the police watchdog's report that reviews the handling of the attacks on law and order in last year's protests, Hong Kong Chief Executive Carrie Lam Cheng Yuet-ngor reaffirmed her commitment on Friday to take resolute action to protect the city's future by ending violence.

The 1,000-page report of the Independent Police Complaints Council, released on Friday, provides insight into the social unrest and exonerated the police of using excessive force in handling the riots.

At a press briefing, Lam said she found it "saddening" to read in the report about the deterioration of the rule of law in Hong Kong in radical protesters' widespread vandalism to public and private property and vigilantism targeting innocent people who held different views.

The report warned about the risk of incipient terrorism and mentioned the deep wounds inflicted by the prolonged violence to the Hong Kong economy and its social fabric.

Lam said the acts of violence have endangered Hong Kong's stability and "one country, two systems". "The rule of law is the cornerstone of Hong Kong's success, and one of the indispensable elements of the rule of law is that members of the public have to abide by the law," she said.

The government and the police will resolutely say no to any violation of the law, and ensure that people will continue to enjoy their freedom and rights within the legal boundaries, she added.

"I believe most Hong Kong people would ask after reading the report: Is Hong Kong still the city we are familiar with? "Lam told reporters.

She also agreed with the report in identifying an often-used tactic of the protesters in spreading hatred online against the police accompanied with threats, intimidations and attack on police officers and their families.

In compiling the report, the IPCC has extensively reviewed the police's handling of key incidents, including the violent clash between protesters and the police in Prince Edward MTR Station on Aug 31. The report called the claims as "untrue death rumors", in which protesters falsely accused the police of using excessive force and resulting in several fatalities.

In another recent case, Lester Shum Ngo-fai, a District Councilor of the opposition camp, accused the police of having "murdered" a college student, who died last November after falling from height in a car park.

In an online post on May 9, Shum called the police as "beasts" and "scums" and called on the public to "avenge" the student's death.

On Friday, police sent a letter to Shum to complain about his slanderous messages and making false allegations to incite hatred and violence. The police added they reserved the right to take further legal action.

The letter, which the police also released on its social media platform, said that the Coroner's Court will conduct an inquiry into the cause of the student's death, and all related documents will be made public.