Taipei (AFP) - Taiwan President Tsai Ing-wen warned Thursday that mainland Chinese who attacked Hong Kongers or damaged "Lennon Walls" could be barred from the island following a recent spate of such incidents.

The walls plastered in colourful sticky-notes, posters and slogans that have sprung up across Hong Kong have also been set up in Taiwan, mostly in university campuses.

However, there have been a number of incidents of Chinese students or tourists damaging the walls or attacking Hong Kong students for posting notes to support the city's democracy movement.

"Such incidents will not be tolerated.The entry of people involved should be restricted to certain degree in the future to maintain our rule of law and social order," she told reporters.

Taiwan held a Hong Kong solidarity rally last weekend which was largely peaceful, although Hong Kong popstar Denise Ho -- a staunch democracy advocate -- had red paint thrown at her by an unidentified assailant as she spoke to local media.

"Do not attempt to provoke Taiwan's democracy and the rule of law.We will not allow such behaviours to continue to happen in Taiwan," Tsai said in a message posted on her Facebook after the incident.

Taiwan has been a de facto sovereign nation since the end of a civil war in 1949, but China still views the island as its territory and has vowed to seize it -- by force if necessary.

Tsai, who is seeking a second term in January, has described the coming election as a "fight for freedom and democracy", setting herself up as someone who can defend Taiwan from an increasingly assertive Beijing.

She has pledged to provide assistance to Hong Kongers facing prosecution for involvement in anti-government protests who seek sanctuary on the island, sparking a rebuke from Beijing to "stop meddling" in the territory's affairs.