Yesterday a court denied him bail over a charge relating to the illegal use of his company's premises.
It comes a day after three prominent pro-democracy activists were jailed.
The cases have raised fears of a renewed crackdown on the city's activists and media figures, spurred by a controversial new security law.
Lai was arrested under the National Security Law earlier this year and later released on bail.
China has said the new law will return stability to the territory after a year of unrest, but critics say it has silenced dissent.
