Born and raised in Hong Kong, Margaret Chan Fung Fu-chun, former director-general of WHO, said she hardly recognized the city now because of the sustained violent attacks on the city's rule of law.

The success of Hong Kong, as a diverse international metropolis, relies on respecting different voices, and resolving the differences through dialogue, Chan said, speaking after attending the morning session of the full-day symposium.

With her voice trembling, Chan said she loves Hong Kong, freedom and democracy.

However, she noted that in her approximately 25 years working as a civil servant under the colonial government, she had never seen so many people free to go on the streets to protest, a right that would not have happened without the Basic Law and "one country, two systems".

She called on the public of Hong Kong to step forward to protect Hong Kong and say no to violence, as Hong Kong is in a dangerous situation now.