A human rights group says two United Nations special rapporteurs have clearly set out a series of major concerns regarding the Hong Kong police force's widespread use of tear gas against anti-government protesters, and the SAR government must respond to the questions raised by the international community, RTHK reports.



Baskut Tuncak, an expert on hazardous substances, and Clement Nyaletsossi Voule who is a special rapporteur on freedom of assembly issues, have published a letter they sent to the Chinese delegation at the UN in January regarding their concerns about the use of tear gas in Hong Kong.



In the letter, they say "we have reasons to believe that tear gas, pepper spray and other chemical agents have been used indiscriminately, unnecessarily and disproportionately, in violation of international and Hong Kong principles on the use of force".



"We also have reasons to be believe that many canisters of tear gas have been used in an uncontrolled and allegedly malicious manner."



They demand, under the mandate given to them by the Human Rights Council, to be provided with a list of information regarding the Hong Kong police's use of various weapons during the protests, including the chemical composition of the tear gas, pepper spray and other chemical agents fired.



They also say they want the Chinese delegation to give them information on what steps have been undertaken to provide urgent relief to individuals and households affected by the various weapons, and the policies for using them near schools and enclosed areas.



"Furthermore, please explain what mechanisms are in place to ensure that the use of tear gas is in line with the principles of proportionality and necessity. Please elaborate what measures have been taken by the government to ensure the physical integrity of the participants and the bystanders of the protests."



Icarus Wong from Civil Rights Observer, which was one of three groups that had urged the UN to look into the issue, welcomed the experts' tough stance.



"Actually I'm quite impressed about this letter. The special rapporteurs use very strong words to question the Hong Kong government," he said.



"I hope that through this communication, the Hong Kong people can understand that what the government is doing lags behind international standards."



Wong said the SAR government and Beijing must now provide the rapporteurs with the information they are seeking.



In response to the publication of the letter on the UN's communications reporting website, the Constitutional and Mainland Affairs Bureau said the SAR had already submitted its reply to the UN through the central government.



The bureau said that it expected its reply to be published on the UN site in due course.