I need to explain what happened before this. Police have been pushing people from street hawkers stalls on Portland Street for several times. Pepper spray, baton, shields were used. Many were dissatisfied about government's policy of not allowing street hawkers, usually present for the 3 days holiday of the Lunar New Year. Both police and protesters have tried to charge (in other posts). When protesters were pushed down to the intersection, they fought back. Then you heard two gun shots - both to the air, which ignited further protest later in the night, until now.