Secretary for Security Chris Tang has warned people against disrupting the national security trial of former media tycoon Jimmy Lai, saying authorities will step up security at West Kowloon Court, where the case will be heard starting on Monday next week.

The minister told reporters that defendants, visitors, and observers will have to pass through X-ray scanners when entering the court.

"We notice that many people who call themselves 'auditors' will harass our prosecutors by making loud noises or following the lawyers to toilets. Some even shout in the court and disturb the hearing," Tang said.

The security chief said the authorities would take immediate and decisive action if anyone tries to disrupt the trial or intimidate anyone involved in it.

Tang also commented on new arrest warrants issued on Thursday for five more people outside the SAR who are accused of security law violations. National security police have also offered rewards of HK$1 million each for information leading to their arrests.

He urged foreign countries to stop harbouring fugitives, stressing that the warrants were issued based on solid evidence.

"At this moment, some foreign governments may be protecting you because you are their lapdog. But once you are of no use, you will become an abandoned pawn. You will always be a wanted criminal. You will be treated like a street rat and will never see the light again," he said.

Meanwhile, the Commissioner's Office of the Ministry of Foreign Affairs in Hong Kong said it "strongly disapproved of and firmly rejected” comments by US and UK politicians on the issuing of the arrest warrants for the latest overseas national security suspects.

In a statement, the office claimed that the five suspects had "challenged the bottom line of the 'One Country, Two Systems' principle, endangered national sovereignty, security and development interests".