Shenzhen police have arrested the suspected mastermind and six accomplices behind the plot to shoot former Democratic chairman Martin Lee Chu-ming and tycoon publisher Jimmy Lai Chee-ying. The accused mastermind, Tung Nga-man, is a Hong Kong resident, the Sunday Morning Post has been told by Shenzhen police officers familiar with the case. It is unclear whether his six alleged accomplices are Hongkongers or mainlanders, but all have strong links to Hong Kong's triad societies, a person familiar with the matter said. The case, scheduled to go before a Shenzhen court on Thursday, comes nearly seven years after the murder of businessman Harry Lam Hon-lit in a Central tea house. 'It's quite similar to the Luk Yu tea house case, with Hongkongers targeting Hongkongers,' said a Shenzhen police officer. Lam, a 54-year-old businessman, was shot at point-blank range as he ate breakfast in the Stanley Street tea house on November 30, 2002. Mainland hitman Yang Wen was hired by a Hong Kong man, who was in turn paid by a Hong Kong triad boss. The seven arrests come two weeks after a mainland gunman, Huang Nanhua, was jailed for 16 years for the planned attack on Mr Lee and Mr Lai. Huang's friend, Hong Kong resident Ho Wai-kam, was jailed for three years for smuggling a gun and bullets into Hong Kong from Shenzhen. At the time commentators called on investigators not to let the case stall. Police had said their investigation was ongoing and that more arrests were possible. When Huang was arrested in a police roadblock on August 14 last year, he was carrying a gun, five bullets and the personal details of Mr Lee and Mr Lai, whose company publishes the top-selling Chinese-language newspaper Apple Daily. Jurors heard that Huang was hired by a shadowy mainland boss to 'teach someone a lesson', whom prosecutors said was most likely Mr Lee. That boss was not identified. It was unclear if two of the six accomplices arrested were the men caught on closed-circuit television footage meeting Huang in a branch of McDonald's in Tsim Sha Tsui just one day before he was arrested. A Hong Kong police spokeswoman said she could not confirm the arrests and would not comment. Mr Lee, founder of the Democratic Party in Hong Kong, said he had been told about the arrest of the alleged mastermind. 'If this guy really is the mastermind, this is a big step forward in the investigation.' Mr Lee said it was logical the mastermind had come from Shenzhen, where Huang also lived. He said he had no obvious enemies with triad connections. James To Kun-sun, vice-chairman of the Legislative Council's security panel, said it was not yet clear if Tung was the mastermind or just an intermediary. 'We will have to evaluate all the facts and see whether they have caught the real mastermind who organised the plot,' he said.