BEIJING (AP) — Friends of prominent Chinese feminist activist Huang Xueqin say she has been detained after returning to the mainland from Hong Kong and Taiwan.

Huang's friends say police in Guangdong province's Guangzhou city arrested Huang last Thursday on suspicion of "picking quarrels and provoking trouble," a vague charge commonly used against activists viewed as threatening by the ruling Communist Party.

The friends say Huang's family was harassed after she published an essay describing her experience at a protest in Hong Kong, a semi-autonomous Chinese city that has been roiled by months of anti-government demonstrations.

In August, Guangzhou police confiscated Huang's passport and other travel documents, preventing her from pursuing a postgraduate program at the University of Hong Kong.

Huang has been an outspoken voice in China's #MeToo movement.