BEIJING (BLOOMBERG) - Hong Kong's High Court's decision to grant bail to media tycoon Jimmy Lai is "unbelievable," according to a commentary in the mouthpiece of China's Communist Party, which warned there are legal grounds for the case to be transferred to the mainland.

The People's Daily called the 73-year-old Next Digital Ltd founder "notorious and extremely dangerous."

Prosecutors this month charged Lai under a sweeping national security law imposed by Beijing in June, saying he colluded with foreigners by calling for sanctions against China.

A judge earlier denied bail while giving the prosecution more time to examine media interviews and about 1,000 tweets for more evidence. Hong Kong's High Court later granted Lai bail of HK$10 million (S$2 million) on Dec 23 on the condition that he stay in his house and avoid giving interviews or posting on social media. He also had to surrender his travel documents.

It's not difficult for Lai to forfeit bail and abscond, the People's Daily said, citing his wealth and "motives" of foreign forces.

Lai's arrest and a dramatic police raid on the newsroom of his pro-democracy Apple Daily paper in August prompted an outcry from foreign governments including the UK, which said the new security law was being used to crack down on press freedoms in the former British colony.

There are full legal grounds for China to invoke Article 55 of the National Security Law, the paper said. Article 55 states China can "exercise jurisdiction over a case concerning offence endangering national security" if the case is complex due to the involvement of a foreign country or external elements, or if a serious situation occurs where the Hong Kong government can't effectively enforce the law.

If Lai's case can't be handled in accordance with the law, it will cause a huge shock to the rule of law in Hong Kong and put national security in an extremely dangerous situation, according to the commentary.

The threat voiced in the editorial will add to rising concerns of China's grip on Hong Kong. As the first security law trials prepare to get underway, Hong Kong's independent judiciary is emerging as the last check on Beijing's power.

So far, Hong Kong's judges have continued to demonstrate their independence, but in a clear break from the past, Beijing is now also weighing in on Hong Kong court decisions, praising satisfactory rulings and using friendly media outlets to criticise others.