About 200 members of the Hong Kong Doctors Union and shopkeepers from 24 malls and markets run by the Link Management marched yesterday to the company's office and government headquarters in Central in protest against rent rises. The protesters - who waved banners and chanted such slogans as 'Link is Shameful' and 'Hefty rent rises turn malls into graveyards' - threatened to start a rent strike if the company refused to listen. It was the second day of protest action against rent rises; shopkeepers at Ngau Tau Kok's Lok Wah market staged a half-day strike on Saturday. Doctors operating in Link-managed shopping centres are angry at what they say are hefty rent rises by the company, which they warn could drive them out of business and result in some public estates not being served by a private doctor. The doctors union said that each month, two or three of the 200-odd clinics in Link-managed malls were forced out by unaffordable rent rises. President Dr Henry Yeung Chiu-fat said the union had received complaints that the Link had increased rents by more than 300 per cent and had imposed a new charge - a 'management fee' - of HK$4 a square foot on top of the new rents. 'It is to force us out of their malls. One day, there could be no private clinics to serve tenants on public estates,' he said. In a statement yesterday, the Link said rents had increased by an average 25.2 per cent over the past three years, about 8.4 per cent a year. It said 73 per cent of shopkeepers renewed their tenancies in 2008-09, showing many found the rents affordable. The Link, a publicly listed real estate investment trust, took control of 180 shopping centres, fresh-food markets and car parks in 2005 when the Housing Authority privatised commercial spaces on public estates. The preferential rents for clinics previously offered by the authority were also dropped. Democratic Party legislator Fred Li Wah-ming, who joined yesterday's protest, said the Link's new management was not as sympathetic to tenants as the previous one. Nicholas Sallnow-Smith, formerly of Hongkong Land, was appointed the Link chairman in April 2007, succeeding Paul Cheng Ming-fun. Cheng said after his departure that he resigned because he opposed the board's plan for big rent rises.