[10][11] On 18 November the police shot 1,458 canisters of tear gas at protesters as well as 1,391 rubber bullets, 325 bean bag rounds, and 256 sponge grenades.

[12][13] On 19 November the city's hospitals were overwhelmed by the number of protesters needing urgent medical attention caused by the siege, and advised citizens not to use emergency rooms unless absolutely necessary.

Among the people arrested were university staff, reporters, social workers, volunteer first-aid personnel, doctors and nurses.

Dr Arisina Ma, president of Hong Kong Public Doctors’ Association, criticised the police for arresting and detaining them for 24 hours and then forcing them to post bail instead of simply checking their professional identification and releasing them.

Polytechnic University authorities released a statement saying that protesters had damaged its laboratories and stolen dangerous chemicals.

[22] At 9:00 am, an RTHK reporter preparing to relieve a colleague inside in accordance with procedures predetermined by the police went to the indicated place for swapping out.

Riot police shouted at the journalist and ordered him to put his hands up while they checked his press ID and identity card.

Other reporters of RTHK who passed the Cross-Harbour Tunnel and wanted to document the events unfolding at PolyU were likewise blocked and ordered to leave by the riot police.

[27] Riot police trapped protesters inside the university as the standoff continued, with students desperate to escape from campus.

[33] Amid dwindling numbers of protesters in the university, the police entered on 28 November to look for stragglers and to clear the premises of hazardous materials.

[44] On 11 February 2023, Alvin Cheng was sentenced to three years and eight months in prison on a rioting charge added by prosecution mid-way through the trial; local media reported that seven others were sentenced to between 7 and 13 months for attempting to help protesters escape the besieged campus, three of whom had pleaded guilty to the perverting public justice charge.

[46][47] A 20-year-old man was sentenced on 27 March 2023 to a training centre after having been found guilty of rioting in Yau Ma Tei to support the besieged protesters on 18 November 2019, when he was 17.

[51] On 18 July, twelve defendants aged between 22 and 32 who had been intercepted in Yau Ma Tei on 18 November 2019, and who had pleaded guilty to rioting, were sentenced to between three years and 40 months.

[53] Teng Jin-guang, president of Polytechnic University, released a video early on 18 November to explain his disappearance and asked protesters to leave peacefully.

Hu Xijin, the chief editor of Global Times, a Chinese state-owned tabloid, urged for violent protesters to be shot and advocated for immunity from charges for the police in the case of a fatal shooting.

[56] A spokesperson for Prime Minister Boris Johnson said that the UK government remained "seriously concerned" about events in Hong Kong and urged for "calm and restraint".