The 63-year-old Hong Kong protester known to many as “Grandma Wong” is reportedly facing criminal charges in the mainland Chinese city of Shenzhen, according to Hong Kong outlet Stand News (link in Chinese).

Alexandra Wong was often seen at protests over the summer, always waving her Union Jack and regularly staying long hours on the streets. She previously told Quartz that she was born and raised in Hong Kong but usually lives in Shenzhen, and regularly crosses the border to take part in the city’s protests. However, she has not been seen in Hong Kong since Aug. 11, when was seen on the ground surrounded by riot police at a metro station that had just been stormed by officers. Since then, protesters have expressed concern online over her safety and a crowdfunding campaign was launched to finance a search for her.

This week, Stand News reported that it had received an email dated Jan. 9 believed to be from Wong with updates on her current whereabouts. She wrote that she had been detained by mainland Chinese authorities in mid-August and charged with “picking quarrels and provoking troubles,” a crime with no clear legal definition that is nonetheless often used in China against anyone from feminist activists to lawyers, artists, and writers. Her email suggests that she spent a month in a detention center in Shenzhen, and later received several days of “patriotic education.”

A portion of her email is written in English. “Have been released from the small cage. Now!!! Be inside the big cage!!! The sky is so grey. I cry everyday, have been prohibited to have Known and My-say,” it reads in part.

Stand News said that it has not been able to independently confirm whether Wong has regained her freedom. In September, pro-democracy lawmaker Eddie Chu said he had been informed by Hong Kong’s Security Bureau that Wong was “safe” (link in Chinese).

In an email to Quartz today (Jan. 10) sent from Wong’s email account, she wrote that “right now, the likelihood of me being detained isn’t considered high…but the possibility that I’ll be disappeared is not non-existent.” She also noted that while she could not divulge too many more details about her experiences over the past five months because she is currently under strict surveillance, her situation has “many similarities” with those who have previously been detained in mainland China.