China's top official in charge of Taiwan affairs Saturday wrapped up a landmark four-day visit to the island marred by angry protests, which forced him to scrap some engagements.

The visit by Zhang Zhijun, the most senior Chinese official ever to visit Taiwan, was a further sign of warming ties between the former bitter rivals despite vocal opposition from Taiwanese suspicious of closer ties with Beijing.

But protests by anti-China demonstrators forced Zhang to cancel a visit to a fishing port in southern Kaohsiung city earlier Saturday following clashes between protesters and the police.

One protester splashed a bottle of white paint on his car late Friday.

Zhang, who holds ministerial status, also scrapped two planned engagements in central Taichung city ahead of his departure, officials said.

Television footage showed a man with a bloody face outside a temple in Taichung who was apparently injured in a scuffle with Zhang's supporters -- even though the Chinese official cancelled his visit to the site.

"Taiwan is a diverse society and there all kind of voices. It is very normal. I believe the consensus of the two sides and the mainstream public opinions are for peaceful developments," Zhang said in Taichung when asked about the protests.

Kaohsiung mayor Chen Chu, a senior politician at the China-sceptic opposition Democratic Progressive Party, urged protesters to refrain from violence.

"Throwing paint is not the way Taiwanese treat their guest. Taiwanese should be more confident and rationally express their different voices and opinions," she told reporters.

She also promised to investigate claims by some protesters that they were mistreated by the police.

- 'Concrete progress' -

Many Taiwanese remain wary of closer relations between Taipei and Beijing. A planned pact to free up the services trade with China sparked an occupation of Taiwan's parliament and mass street protests in March and April.

Opponents have accused the government of trading Taiwan's national interests to Beijing in exchange for marginal economic benefits.

Eight protesters were arrested on Thursday for trying to blockade Zhang while he was visiting a scenic mountain region near Taipei.

On Wednesday, dozens of pro-independence and pro-unification activists clashed at the airport before police separated them. Demonstrators also tried to break through security barriers and clashed with riot police outside a hotel where Zhang was meeting his Taiwanese counterpart Wang Yu-chi.

No official documents were signed at the meeting, but Wang noted that some "concrete progress" was made, saying the two sides formally agreed to discuss the issue of giving representatives the right to visit nationals detained or jailed by the other side.

Zhang and Wang had met in China's eastern city of Nanjing in February in the first government-to-government talks since Taiwan and the mainland 65 years ago after a civil war.

China considers self-ruled Taiwan as a part of its territory awaiting reunification -- by force if necessary.