A 38-year-old man was in police custody last night after being arrested in connection with one of four recent attacks aimed at the Chinese-language newspaper Apple Daily.
The man was picked up in Yuen Long on Wednesday night on suspicion of arson and criminal intimidation.
A police spokeswoman said the man was suspected of being linked to the latest attack - the fourth in 11 days - in which three assailants threatened two people with knives in Edinburgh Place, Central, on Sunday, before burning copies of the newspaper.
The suspect is understood to be the owner of a car used in the attack.
According to a police source, the suspect claims not to have used the car since his business partner borrowed it last year. Investigators last night were trying to track down the partner, and a senior officer said more arrests could be made.
The suspect in custody is understood to have a criminal record involving handling stolen property and untaxed goods.
Police declined to say yesterday what role he was suspected of having played in the attack. Last night, the man was being held for questioning in Kowloon City police station and had not been charged.
It was the first arrest since the attacks started on June 19 - when attackers rammed a stolen car into the front gate of media mogul Jimmy Lai Chee-ying's house in Mong Kok and left an axe and a machete in the drive. Lai (pictured) is chairman of Next Media, publisher of Apple Daily.
A week later, two knifemen threatened two delivery workers and torched bundles of the newspaper on board a truck in Hung Hom.
On Saturday, a machete was found outside the Next Media building in Tseung Kwan O.
Next Media has offered HK$1 million to track down the assailants and the mastermind behind the attacks.
The news group has been highly critical of post-handover Hong Kong governments and backs calls for more democracy.
Lai said on Sunday that he and his company would not be scared off by "childish acts" and the newspaper's editorial policy would not change.