Three families of imprisoned Hong Kong youth arrived in Shenzhen on Sunday morning hoping to visit their loved ones after 14 days of forced quarantine.
Chu Hoi Dick, a former democratic lawmaker who is helping her family, said her relatives had little information about the detainees.
He urged the Hong Kong government for help.
“At least they can help relatives clarify the rather complex requirements of different detention centers. There are special rules or visit dates, especially during this pandemic. It is very difficult for relatives themselves to access or get answers to information. I think comes first,” he said.
In response, the Bureau of Security said it would not help families make such arrangements or accompany them to visits according to past practice.
However, the official stressed that he would try to find more information about the problem and pass it on to relatives.
Families have in the past accused the Security Bureau of doing nothing to help detained Hong Kongers, such as guaranteeing the right to appoint an attorney or to a public trial.
The government has repeatedly refused to intervene in high-profile cases, stating that it "will not interfere with law enforcement and judicial affairs in other jurisdictions."
Ten of the inmates were sentenced to 7 to 3 years in prison last week while crossing the mainland while trying to flee to Taiwan in August.
The other two prisoners, who were minors, were sent back to Hong Kong.
All of them have been arrested in the SAR for protest-related charges or for violating national security laws.