Hong Kong media tycoon and pro-democracy advocate Jimmy Lai was denied bail on Saturday after being charged the previous day under a new national security law. 

Lai was charged with collusion with foreign elements to endanger national security, for tweets he wrote and interviews he made with foreign media. 

Lai founded the pro-democracy Apple Daily tabloid, and has made visits to the US, including a meeting with US Secretary of State Mike Pompeo. 

The Apple Daily said he is accused of asking a foreign country, organization or individual to impose sanctions or engage in other hostile activities against Hong Kong or China. He has been in custody since last week. 

If convicted, the 73-year-old faces a possible maximum sentence of life in prison. The newspaper said his charge sheet listed several foreign politicians who followed Lai on Twitter and cited commentaries he wrote and interviews he gave to foreign press.

Lai was seen handcuffed to a chain around his waist as guards led him to a van to go from prison to court. 

'A mockery of justice'

Pompeo tweeted Saturday morning that the security law "makes a mockery of justice." He called for Lai's release, saying his only crime is speaking the truth about China's authoritarian Communist Party government. 

Lai also spent two days in police custody earlier in the year when his company, Next Digital Media, was raided by hundreds of police officers under the security law.

Trials are heard by judges selected by the city's Beijing-backed leader, Chief Executive Carrie Lam.

The law, which targets secession, subversion, terrorism and collusion with foreign forces, was imposed by Beijing in June, bypassing the city's elected representatives. Critics say the law is a method to quash dissent. 

This week alone, 16 pro-democracy supporters were arrested under the legislation. 

lc/mm (dpa, AP)