Police in southern China have arrested seven men including the suspected mastermind of a foiled gun plot targeting veteran Hong Kong democrat Martin Lee and media tycoon Jimmy Lai, a newspaper reported on Sunday. The South China Morning Post newspaper cited unnamed police sources in the southern Chinese boomtown of Shenzhen as saying they arrested a Hong Kong man suspected of being behind the plot, along with six alleged accomplices with links to organized criminal gangs. "It is unclear whether his six alleged accomplices are Hong Kongers or mainlanders, but all have strong links to Hong Kong's triad societies," the newspaper cited a person familiar with the matter as saying. The arrests come weeks after a mainland Chinese man who traveled to Hong Kong from Shenzhen was jailed for 16 years for carrying a gun with intent to harm Lee, a leading figure in the territory's political development before and after 1997, when the former British colony reverted to Chinese rule. The man was arrested during a routine road block. Jimmy Lai, the Hong Kong publisher of Apple Daily, a pro-democracy tabloid, was also reportedly targeted. Despite the arrests in China, Lee said he did not know the alleged mastermind, and that the true perpetrators of the plot may still be at large. "Unless the police find out the motive behind the plot, I don't think police should close the file but continue to investigate until they identify the real mastermind," Lee told Reuters. Lee added that neither the Hong Kong nor Chinese police had informed him of the recent arrests. A Hong Kong police spokeswoman would not comment except to stress there was "close cooperation" with police in mainland China in fighting crime.