Ten of 12 Hong Kong democracy activists arrested at sea as they tried to flee to Taiwan by speedboat have gone on trial in mainland China.
The hearing was closed to foreign reporters and diplomats but the court said in a statement that both prosecution and defence lawyers spoke.
Court was adjourned with no verdict.
The activists were caught in August in a rare attempt at escaping the city after a harsh new security law was introduced by Beijing in June.
China has a history of putting dissidents on trial around the Christmas period to avoid international scrutiny. But the high-profile nature of this case drew sharp criticism in the hours before the trial started, with the US embassy in China urging the "immediate release" of the activists.
"Their so-called 'crime' was to flee tyranny," a US embassy spokesperson told the AFP news agency ahead of the hearing.
The Chinese ministry of foreign affairs responded, calling on the US to "immediately stop interfering in China's internal affairs through the Hong Kong issue".
Two of the 12 dissidents are underage and will face private hearings on a separate date.
The 12 Hong Kongers - aged 16 to 33 - were intercepted at sea by the Chinese coastguard on the morning of 23 August, just 40 miles (70 km) southeast of Hong Kong.
Most of those on board were already facing charges at home linked to the huge pro-democracy protests that swept the former British colony last year.
That meant they could not leave the territory by regular means.
At least one of the activists was being investigated under the controversial national security law.
The case of the 12 detainees has highlighted the growing struggle for democracy activists in Hong Kong, which was once a key destination for refugees fleeing persecution.
What do we know about the case?
For months after their arrests the activists were held in detention without charge in the mainland city of Shenzhen.
A few weeks ago Chinese authorities finally charged 10 of the group: eight have been accused of illegally crossing the border, which carries up to a year in jail, while two face the more serious charge of organising the crossing, punishable by up to seven years.
The defendants were expected to appear via video link at the hearing on Monday afternoon from the centre where they are detained, though details about the proceedings were not released.
Families barred from hearing
The families of the activists have expressed their fears about the fates of the detainees in China's notoriously opaque judicial system.
The Chinese lawyers some of them had hired were barred from seeing their clients as authorities stepped in to appoint state-approved counsel, according to AFP.
Over the weekend the families published an open letter to the international community, appealing for its help to "safeguard the legal rights" of the detained 12.
They called for the hearing to be broadcast live, after they were barred from appearing in person because of Covid-19 restrictions, and only notified of the trial date on Friday.