POLITICAL commentaries written by magazine publisher Jimmy Lai Chee-ying are being studied by police investigating this week's fire-bombing and vandalism of his home and offices. A police source confirmed the investigation would centre on articles and advertisements published in his best-selling Next magazine. ''It will take us time to investigate the cases because we need to read every article and advertisement published in the past six months,'' he said. ''The articles will include film reviews, political commentaries, Mr Lai's personal column, editorials and stories about people's personal life. ''We are paying particular attention to the magazine's cover stories in an effort to find out connections to the threats Mr Lai and his companies face.'' The source said police had not been able to establish whether the fire-bombing and vandalism were targeted at Mr Lai, who also owns the Giordano clothing chain, or his magazine. A man hurled a Molotov cocktail into the driveway of Mr Lai's two-storey house in Tai Po Road overlooking Shekkipmei on Thursday. No one was injured as the fire-bomb landed in the front yard about 12 metres from the villa at Piper's Hill. The day before, the magazine's Quarry Bay office and one of Mr Lai's companies in Lai Chi Kok were smashed up by three men almost simultaneously. Detectives from the Hong Kong Island Regional Anti-Triad Unit are investigating whether triads are behind the attacks. The police source confirmed detectives were at Mr Lai's home and at his two offices at key times of the day. ''Our coverage at his home and two offices concerned is aimed at trying to arrest the culprits if they do come again rather than as personal protection for Mr Lai. ''We don't escort Mr Lai when he goes out, but step up patrols around his house and offices,'' he said.