Hong Kong separatists Joshua Wong Chi-fung and Agnes Chow Ting will stand trial in November after appearing at the city's Eastern Magistrates' Courts on Friday afternoon.

Wong and Chow, both 22, were arrested Friday morning for their involvement in occupying police headquarters in Wan Chai on June 21.

The trial was adjourned to Nov 18.

Both are facing charges of inciting others to participate in an unauthorized assembly and participating in an unauthorized assembly. Wong is facing a third charge of organizing an unauthorized assembly.

They were granted bail of HK$10,000 ($1,275). They will have to comply with curfew orders and are barred from traveling abroad, except for two of their respective pre-planned trips.

The two are from the same political organization – Demosisto – the separatist party of which Wong is a leader and Chow a co-founder.

Aside from Wong and Chow, the founder of a banned separatist party, Andy Chan Ho-tin, was also arrested on Friday morning.

Chan, founder of the Hong Kong National Party, banned for its strident "Hong Kong independence" advocacy, was arrested late Thursday night at Hong Kong International Airport when he was about to leave for Japan.

The 29-year-old was charged with rioting and assaulting a police officer.

On Aug 1, Chan, along with 10 more people, was arrested in two separate crackdowns in Fo Tan, New Territories of Hong Kong.

They are suspected of possessing offensive weapons and explosives without a license.

Chan's arrest was believed to be connected to protests that have taken place in the city since June 9.

In this case, he was eventually released on bail and is due to report to police in September.

Visiting Hong Kong, Hu Xijin, editor-in-chief of the Beijing-based newspaper Global Times, questioned the magistrate's decision to grant bail to the activists. By doing so, the judiciary sent a negative message to the public, he said.

Hong Kong is facing unprecedented challenges, Hu said. Lenience for those who incite, organize and participate in illegal assemblies will hurt the city's rule of law, Hu said.

Meanwhile, police clarified rumors as some members of the public questioned the timing of the arrests, which happened a day before a planned-but-later-banned rally on Saturday.

The date marks the fifth anniversary of the "831 Decision" on Hong Kong's electoral reforms, in which the Standing Committee of the National People's Congress provided an election framework for Hong Kong to elect its chief executive by "one man, one vote".

However, the plan was vetoed by the opposition camp in the Legislative Council.

During a daily press briefing on Friday afternoon, police said that all arrests are based on evidence. The timing of the arrests doesn't have any implications, said Tse Chun-chung, chief superintendent of Police Public Relations Branch.

"If someone breaks the law, the police will bring him or her to justice," Tse added.

The police are politically neutral, Tse said. "We will not consider one's background or political stance when we arrest or prosecute any offender."

The High Court has extended a temporary ban of any action that disrupts services of the city's sole railway operator – Mass Transit Railway (MTR) – until  further notice.

The MTR was granted an interim injunction on Aug 23 to stop people from "unlawfully and willfully obstructing or interfering" with its operations, damaging its property, and causing disturbances at its stations.