The video was shot on 18 November 2019. Several protestors tried to escape from the campus and police fired tear gas towards them, citizens outside the Hong Kong Polytechnic University (PolyU) were crying and pledging the police not to arrest the protestors. The PolyU siege, which lasted for more than 2 weeks, is part of the Hong Kong Anti-Extradition Bill protests in 2019. Protestors took over the university as a defense against Hong Kong Police after setting up roadblocks at Cross-Harbour Tunnel. There were several conflicts among protestors and police, more than 1500 canisters of tear gas were fired, as well as 1,391 rubber bullets, 325 bean bag rounds, and 256 sponge grenades. There were more than 1300 protestors being arrested.