Lawyers for the defendants are challenging a prosecution bid to deny them bail and keep them in custody for up to three months while police investigate.

Democrat and district councilor Clarisse Yeung fainted in the courtroom after midnight and was taken to the hospital by ambulance. Her condition was not immediately disclosed.

Local media reported three other defendants fainted after the hearings were adjourned.

On Monday, about 1,000 supporters gathered outside the West Kowloon courthouse as the defendants, charged under the Chinese-ruled city’s contentious national security law, faced charges after their arrest over the weekend.

The crowd chanted slogans such as “Liberate Hong Kong, revolution of our times” and with many dressed in black, the images were reminiscent of scenes during anti-government demonstrations that roiled the city in 2019.

The activists are accused of organizing and participating in an unofficial primary poll last July aimed at selecting the strongest candidates for a legislative council election that the government later postponed, citing the coronavirus.

Authorities said the informal poll was part of a plan to “overthrow” the government, stoking concerns alarm that Hong Kong has taken a swift authoritarian turn since Beijing imposed the security law on the former British colony in June.

The detentions have drawn international condemnation and accusations that the governments in Hong Kong and Beijing are using the law to crush dissent and stifle the opposition.

U.S. State Department spokesman Ned Price said on Monday Washington called on Hong Kong authorities to release those still held and drop charges against them.

Beijing has said the security legislation, which punishes what it broadly defines as secession, subversion, terrorism and collusion with foreign forces with up to life in prison, is necessary to restore stability in Hong Kong.