Taiwan's main opposition party says it has come under sustained attack by Chinese-based computer hackers seeking information about its plans for next year's presidential elections.

Officials of the Democratic Progressive Party said at least 12 attacks over the past four months have been traced to addresses in China or Hong Kong. They said the attacks targeted the party's campaign plans for presidential and legislative elections set for January.

China has enjoyed improving relations with Taiwan since President Ma Ying-jeou of the Beijing-friendly Nationalist Party came to office in 2008. It has had much more difficult relations with the DPP, which supports independence for the island. Beijing wants to reunify it with the mainland.

The California-based computer security company McAfee said last week that a global cyber-spying campaign has targeted 72 organizations in 14 countries, including Taiwan.

McAfee did not identify the source of the attacks, but analysts said it was likely China. Chinese state media labeled that accusation as “irresponsible.”

China and Taiwan have a long history of spying on one another since Nationalist troops fled to the island at the end of China's civil war in 1949.