TAIPEI - A TOP Chinese official who was shoved to the ground by pro-independence activists during a visit to Taiwan left the island ahead of schedule on Wednesday, saying he needed medical treatment.

Mr Zhang Mingqing, vice-president of China's Association for Relations Across the Taiwan Strait, told reporters he was flying back to Beijing for tests.

'The police put a lot of manpower to protect my safety and I feel very bad causing them trouble. This should not have happened,' Mr Zhang said at Kaohsiung airport in southern Taiwan, where he was heckled by more protesters.

'The public will tell right from wrong,' he added.

'This violent incident was caused by a few people. It didn't represent the 23 million Taiwanese people.'

Television pictures showed more angry scenes at the airport, where police arrested a man who was shouting 'Independent Taiwan' among a handful of other protesters.

He was identified by media as a Kaohsiung councillor for the opposition pro-independence Democratic Progressive Party (DPP).

On Tuesday, Mr Zhang was surrounded by protesters, jostled and pushed to the ground while visiting a temple in the southern city of Tainan.

Mr Zhang has filed assault charges against DPP city councillor Wang Ting-yu, said an official at Taiwan's Straits Exchange Foundation.

Wang has insisted Mr Zhang simply tripped.

Tainan's city police chief has been demoted to a job in the police highway bureau following the incident, the National Police Agency said.

The episode triggered an angry response from the Chinese government, which demanded Taiwan severely punish the activists who manhandled Mr Zhang.

Reaction in Taiwan was mixed, with the government condemning the incident while the DPP branded Mr Zhang an 'enemy' of the island.

'Zhang deliberately came to my hometown Tainan... this is the equivalent of a provocation,' former president Chen Shui-bian of the DPP said on Wednesday.

China and Taiwan split in 1949 following a civil war, but Beijing regards the island as part of its territory awaiting reunification.

Mr Zhang's semi-official agency is authorised by Beijing to handle civilian exchanges with Taiwan in the absence of official contacts.

His trip comes as Taiwan is trying to arrange a new round of cross-Strait negotiations, after talks with China in June led to the first regular direct flights between the island and the mainland in nearly six decades.

Ties have improved dramatically since Taiwan's China-friendly president Ma Ying-jeou took office earlier this year. He has promised to improve business and tourism ties with China following eight years of strained relations under Mr Chen.

Mr Zhang's association had written to its Taiwan counterpart to express its 'strong indignation and severe condemnation' of the attack, China's official Xinhua news agency said on Tuesday.

'We are astonished at this,' it cited the letter as saying. -- AFP, REUTERS