For a second summer in a row, political unrest turned to the streets of Hong Kong.

Hundreds of protesters were arrested in the busy shopping district of Causeway Bay on Wednesday (1 July) after China’s central government imposed a national security law on the semi-autonomous city. Protesters and police also clashed in May and June after the security law was proposed.

The new law significantly expands the powers of local and mainland authorities to investigate, prosecute and punish opponents.

Critics say the law frees Hong Kong from autonomy and valuable civil and social freedoms. China and local governments argue that it is necessary to reduce restlessness and maintain mainland sovereignty.

Last summer, anti-government protests were fired with strong opposition to a proposed extradition law. Critics feared that the bill would allow citizens to be sent to the cross-border mainland of China. Carrie Lam, Hong Kong Chief Executive, withdrew the bill in September, but refused to provide grounds on four demands, including more democracy for the city and an independent police commission.