The National People’s Congress, China’s rubber-stamp parliament, is expected to approve the plan on Thursday, bypassing Hong Kong’s own legislature.

At least 50 people are being held by police outside Hysan Place in Causeway Bay, after crowds marched in the street, chanting slogans in protest of the national anthem bill and national security law.

Earlier in the day, police in riot gear stopped and searched mainly young people outside Hong Kong’s MTR railway stations during morning rush hour and lined walkways as commuters shuffled past, prompting accusations on social media that the city had become “a police state”.

“I’ve come for something I care deeply about – ultimately it’s freedom,” said a 40-year-old lawyer who wished to remain anonymous, citing the national security laws, Beijing encroachment, and a recent report clearing police of wrongdoing.

A 73-year-old woman who gave the surname Cheung said she swam to Hong Kong from China to “escape the dictatorial rule of the CCP [Chinese Communist party]” when she was 15.

Several days have been set aside in the Hong Kong legislature for debate on the anthem law and the vote is scheduled for 4 June – the anniversary of the Tiananmen Square massacre and another source of controversy given Hong Kong’s vigil this year will not be allowed

Booing of the March of the Volunteers, the national anthem of the People’s Republic of China, as well as Hong Kong and Macau, at Hong Kong football marches has previously embarrassed Beijing

Hong Kong media on Wednesday alsl reported that Beijing had expanded the scope of the draft security law legislation to target organisations as well as individuals, according to the public broadcaster RTHK and the South China Morning Post

The EU has said China must respect Hong Kong’s autonomy

Taiwan’s president, Tsai Ing-wen, has said her government would come up with measures to help Hong Kong residents, fearing for their safety under the new law, relocate to Taiwan

The commander of the People’s Liberation Army garrison in Hong Kong said earlier this week his troops – estimated to number around 10,000 – stood ready to “safeguard” Chinese sovereignty and support national security laws