HONG KONG (Reuters/AFP) - The home and former offices of Hong Kong media tycoon Jimmy Lai, an outspoken critic of Beijing who also played a prominent role in large pro-democracy protests last month, were firebombed early on Monday, a spokesman said.

The first attack took place around 1.30am local time, when an unknown car reversed up to Mr Lai's house and threw an object that exploded into flames when it hit the gates. About 20 minutes later, one or two other incendiary devices were thrown at the gates of Next Media.

"This is a continual effort to try to intimidate the press in Hong Kong," said Next Media spokesman Mark Simon. "This is raw and pure intimidation."

"Anti-democratic forces in Hong Kong keep resorting to violence," Mr Simon added.

"Violence and intimation seem to be the ongoing currency for those opposed to democracy and free press. There is no other plausible explanation here."

Such acts will not be tolerated "no matter what social status or political background, or political views (of any individual)", Secretary for Justice Rimsky Yuen told reporters. He said police will investigate the firebombing like any other criminal act. Some feel that Hong Kong police don't always follow up fully on acts against the city's democrats or against Apple Daily, and that culprits are rarely found.

The Hong Kong police confirmed they are looking into two incidents, one at a residence on Kadoorie Avenue in Kowloon and one at the offices of Next Media. "The cases have been classified as arson. We are still verifying the details," a police spokesman told AFP. The police have made no arrests so far and investigations were under way, she added, without giving further details.

There were no reports of injuries and images from the scenes show no significant damage to the buildings. The South China Morning Post website said that both incidents had involved petrol bombs and that no-one had been injured. Blurred images on the website showed a masked man standing beside a sedan throwing a flaming object towards Mr Lai's home in the upmarket neighbourhood of Ho Man Tin in Kowloon. Two cars suspected to have been used in the attacks were later found torched, the SCMP said.

Security camera footage uploaded to the Apple Daily website shows a masked man throwing a flaming glass bottle towards the gate of Mr Lai's mansion. It explodes on the ground outside as the suspect flees in a car.

Footage from outside the Next Media headquarters in a suburban industrial park also shows a flaming bottle thrown towards the building entrance and smashing on the ground.

Mr Simon said the attacks were "more depressing than shocking" for Hong Kong and the free press.

He added that Mr Lai, 66, had been told of what happened and quickly went back to bed.

"He is psychologically prepared for anything. It's Jimmy Lai," Mr Simon told AFP.

Mr Lai, who stepped down as chairman of Next Media and as publisher of the popular, pro-democracy Apple Daily tabloid in December, is a well-known critic of Beijing. He was arrested for refusing to leave a pro-democracy protest site in central Hong Kong last month as police cleared protesters who had shut major thoroughfares in the city for 21/2 months.

A self-made millionaire, Mr Lai is a long-time supporter of Hong Kong's democracy movement.

The firebombings take place against a backdrop of increased vigilance at media organisations across the globe in the wake of the deadly attacks on the Charlie Hebdo satirical magazine in Paris.

Mr Simon emphasised that they "in no way compared" to those in France, but voiced his fears over the violence.

"Peaceful disagreement has been a norm in Hong Kong for so long. Pro-government supporters should really think twice about this kind of violence being imported to Hong Kong over political issues."

The attacks also came as tension remains high in the southern Chinese city after more than two months of protests for free leadership elections, which ended when rally camps were cleared in December.

Mr Lai was targeted during the protests by a group of men who threw rotten meat at him and printworks producing his outspoken Apple Daily newspaper were repeatedly attacked.

He was arrested at the clearance of the main Admiralty protest site in December and has been asked to appear at a police station later this month to help with the investigation into the demonstrations.

In 2013, masked men torched tens of thousands of copies of two Apple Daily editions at distribution points.

Last year, Next said HSBC Holdings and Standard Chartered had pulled millions of dollars worth of advertising from Apple Daily after being pressured by Beijing, decisions both banks said were commercial.

Mr Lai's home has been attacked before, including being rammed by a car and having a machete, axe, and threatening messages left in his driveway.

He remains the majority shareholder in Next Media, which publishes Next Magazine and the Apple Daily.