A 63-year-old Hong Kong protester who disappeared from the rallies last August has said she is detained in China, barred from leaving the country and facing criminal charges.

Alexandra Wong, who is nicknamed “Grandma Wong,” has for years been a fixture at protests in Hong Kong, where she was born.

Ms Wong, who now lives in Shenzhen, a neighbouring Chinese city, would travel near-daily across the border to participate in political demonstrations in the former British colony, often waving a Union Jack flag to urge the UK government to do more to protect freedoms in Hong Kong.

She was last seen on Aug 11, surrounded by riot police at a Hong Kong subway station.