This post is a round-up of a series of posts – Violence erupts across Hong Kong as police fire ‘warning shots’  on September 1 and HKFP Lens: Hong Kong police crackdown with water cannon, tear gas as protesters hurl Molotov cocktails at gov’t HQ  and Hong Kong police water cannon truck fires blue-coloured water as protesters besiege gov’t HQ  – published on Hong Kong Free Press between 31 August and 1 September 2019. It is republished on Global Voices under a content partnership agreement.
Violent clashes erupted across Hong Kong after tens of thousands defied police bans and joined the “unauthorized” weekend rally on 31 August 2019.
The rally was initiated by the Civil Human Rights Front to reiterate the demands of the anti-extradition campaign and to denounce Beijing’s intervention in Hong Kong’s political reform. The date is significant as 31 August marks the fifth anniversary of a decision made by the Standing Committee of National People’s Congress which sought to impose a screening mechanism for the future election for Hong Kong’s chief executive.
‘Prayer walk for sinners’
Although the CHRF was forced to cancel the official planned march after police refused to issue a permit, thousands of people defied the police ban and joined a “prayer walk for sinners” at Southorn Playground in Wan Chai.
Christopher Yeung, a Catholic who was leading the march, told HKFP that the march was not a protest but a religious gathering. Under the Public Order Ordinance, religious activity does not require police endorsement as long as there are less than 30 participants.
But thousands appeared at the Southorn Playground and walked towards the police headquarters in the early afternoon, then moved on towards Admiralty and Central. More people joined in resulting in the halting of traffic on major roads from Causeway Bay to Central. Police officers raised yellow flags at various spots warning crowds that they were breaching the law and could be prosecuted. But people kept on walking in the streets.
Escalated violence: batons and pepper spray in a subway carriage
Majority of the protesters left around 5:30 pm and violent clashes broke out as more radical protesters attempted to besiege the Legislative Council. Riot police fired tear gas and launched water cannons while protesters hurled objects at police lines, including Molotov cocktails.
Saturday’s outpouring comes a day after mass arrests of prominent activists and political figures  for offences related to inciting, organising or attending an unauthorised assembly. Those rounded up included pro-democracy lawmakers Cheng Chung-tai, Au Nok-hin and Jeremy Tam, as well as activists Joshua Wong, Agnes Chow and founder of banned pro-independence Hong Kong National Party Andy Chan.
As night fell, riot police advanced along Hennessy Road. Near police headquarters, protesters built a huge fire, which was eventually put out by the fire brigade.
At around 9:30 pm police started arresting protesters. Undercover police officers fired two warning shots as they were outnumbered by the protesters when they attempted to conduct arrests in Causeway Bay.
As protesters dispersed, violence spilled over around Kowloon’s Yau Tsim Mong district as police deployed tear gas in Prince Edward. Clashes also broke out in Kwun Tong and Lam Tin.
Upon receiving reports from the MTR on a clash inside a train carriage  as about 3-4 passengers stopped the protesters from entering the carriage with metal rod and hammer while the protesters fought back with umbrellas and a fire extinguisher. Riot police officers then charged onto the platforms of Mong Kok and Prince Edward MTR station to conduct arrests.
TV news footage showed riot police beating people with their batons inside train carriages at Prince Edward station and deploying pepper spray, with many passengers seen to be cowering and bleeding.
In a statement, the government claimed that protesters were vandalising stations and attacking members of the public, and officers had entered MTR stations to “stop all violent acts and arrest offenders.”
However, video footages shows that riot police were beating up people who were not acting violently. Vice-Chairman of the Democratic Party Lo Kin Hei described the police violence on the subway train as an authorized version of mob attack  on 21 of July in Yuen Long:
The horrible scene at Prince Edward Station where Police Raptors rushed into the MTR train cart, and beat up anyone in there with totally no harm & no sign of defiance. Just the same as the 7.21 Yuen Long Attack carried out by mobs. pic.twitter.com/nTfBb1ehG4 
— LO Kin-hei 羅健熙 (@lokinhei) August 31, 2019 
The hospital authority reported  that 41 were hospitalized and 5 suffered from serious injuries during the weekend clashes.