 Complete the following phrase:  Against the backdrop of the intensifying 201920 Hong Kong protests, another march was held on 21 September 2019 by protesters who alleged that the dai ma had returned to the park. Police had initially banned the event, but the ban was overturned on appeal. Tuen Mun station was pre-emptively closed by the police. Protesters marched from San Wo Lane Playground, through Tuen Mun Park, to the Tuen Mun Government Offices, where they burned the flag of the Peoples Republic of China. The police cut the event short and undertook a dispersal operation, firing tear gas and sponge grenade rounds at protesters, some of whom threw Molotov cocktails. Light rail and MTR bus services in the area were subsequently suspended. Protests spread to the nearby town of Yuen Long that evening, marking the two-month anniversary of 