HONG KONG (BLOOMBERG) - Hong Kong police raided the private offices of media tycoon and activist Jimmy Lai, a top executive at his company said, months after he was arrested under a new national security law and the newsroom of his pro-democracy newspaper was stormed.

Fourteen officers raided the Next Digital founder's offices, took documents and departed before a lawyer arrived, Next Digital group director Mark Simon tweeted on Thursday (Oct 15). Mr Simon said police had promised to stay until the lawyer was on site.

Police are "still trying to make civil disputes into criminal cases and more ominously shut off funds Mr Lai uses to support Apple Daily", Mr Simon wrote.

He didn't provide further information.

A public relations representative for the Hong Kong Police Force did not immediately respond to a request for comment when reached by Bloomberg News.

Shares of Next Digital jumped as much as 38 per cent in afternoon trade. The media company had soared more than 1,100 per cent over two days in August as people bought the stock to show their support for Lai after his arrest.

Lai's arrest this summer under the sweeping new security legislation enacted by Beijing sent shockwaves through a city where the safety of basic freedoms of speech are being increasingly questioned. So did a raid by dozens of officers on his flagship paper, Apple Daily, which was streamed on live video.

In a separate case, Lai was last month found not guilty of criminal intimidation of a reporter in 2017. He still faces multiple criminal investigations related to his participation in Hong Kong's democracy movement.