Lien Chan, who was also previously premier and chairman of the ruling Kuomintang (KMT) party, was accompanied by his wife and 10 other politicians to Thursday's event in Tiananmen Square marking the 70th anniversary of Japan's defeat in World War II, defying President Ma Ying-jeou's advice to stay away.

Dozens of slogan-chanting protestors clashed with police as Lien arrived back at Taipei airport at midnight after attending the event.

"How dare Lien Chan come back to Taiwan after he did this shameless thing to Taiwan people?" a protest leader told reporters as the crowd branded Lien a "traitor" and shouted that he should "get back to China".

Annette Lu, another former vice president and member of the China-sceptic Democratic Progressive Party (DPP), filed a law suit against Lien in the High Court on treason charges.

Fury also came from within the KMT, with current chairman Eric Chu saying the party will look into the matter as a growing number of members demanded Lien be disciplined.

The ruling KMT and China's communist government have long disagreed over who should take the credit for victory against Japan in 1945.

The Kuomintang troops led by Chiang Kai-shek fled the mainland four years after the end of WWII, and after a civil war that saw them crushed by the Chinese communist forces led by Mao Zedong.

During a meeting with Chinese president Xi Jinping on Tuesday, Lien credited the Chinese communist forces with winning the war against Japan in contrast with the KMT's argument that their troops, then the rulers of China, fought all the major set-piece battles against Japan.

In reaction, President Ma said he felt "regret" and that Lien's move "had deviated from the country's position and missed the expectation of our country people."