Marchers flew American flags to celebrate final passage of the U.S. Hong Kong Human Rights and Democracy Act. They also carried the pre-1997 Hong Kong flag, which includes a Union Jack canton.

In the 22 years since it was first raised, Hong Kong’s flag and flower emblem have become targets for pro-democracy activists.

The Hong Kong Special Administrative Region (HKSAR) government held a flag-raising ceremony and a reception to celebrate the 28th anniversary of Hong Kong’s return to the motherland on Tuesday ...