HONG KONG - Chinese President Hu Jintao on Sunday swore in Hong Kong's new leader while calling on him to resolve "deep disagreements" ranging from recent government scandals and political discord in the free-wheeling financial centre after a year of transition. Security was tight at the same harbour-front venue where the British handed Hong Kong back to Communist Party-run China exactly 15 years ago, with hundreds of police forming a solid ring fence to ensure the isolated demonstrations were kept out of sight and earshot. Hu expressed China's confidence in Hong Kong's role as a free, law-abiding society, though in a sign of Beijing's anxiety over recent tensions, he appealed for unity and called on the administration of Leung Chun-ying, who was sworn in for a five-year term, to heed the recent social schisms. "While we recognise Hong Kong's achievements 15 years after the handover, we must also be conscious of the deep disagreements and problems in Hong Kong society," Hu said. A lone protester stood and heckled Hu as he spoke, demanding an end to one-party rule and dictatorship in China, before being wrestled away by nearly ten security personnel. Outside the venue, masses of Hong Kong police and high barricades smothered all attempts by protesters to approach. Several demonstrators were taken away in a police van while a truck draped with black June 4 slogans denouncing Beijing's bloody crackdown on protesters in 1989 was forced away and tailed by a police motorcycle. "Hong Kong has freedoms, and we have the right to protest! Why do you even stop us from walking?" lawmaker Lee Cheuk-yan shouted into a loud hailer as he harangued police blocking him and other activists. Hong Kong is a liberal, global financial hub agitating for full democracy, making it both an asset and a potentially dangerous precedent for China where people are becoming increasingly intolerant of rights abuses and curtailed freedoms. More than 100,000 Hong Kong citizens later hit the streets in an annual mass July 1 protest, sending a defiant message to China's leader that the city cherishes its freedoms in the face of perceived Beijing meddling in its domestic affairs, and calling for unfettered democracy in 2017. "Hong Kong's human rights record has backtracked," said one of the demonstrators, Theresa Cheng, a 20 year-old university student. "Freedom of speech is shrinking and reporters are facing more obstacles." Other issues stoking citizen anger include an illegal construction scandal that has badly hit Leung's integrity and popularity, a yawning wealth gap, corruption and pollution - though Sunday's events were held under a sunny blue sky. Praised as one of the world's freest and simplest low-tax havens for conducting business and a gateway to China, Hong Kong has nevertheless struggled over the past 15 years, with critics accusing Beijing of extensive behind-the-scenes meddling in political, electoral, academic, media and legal spheres. This year saw a fraught, mud-slinging electoral race for the city's top job that was eventually won by Leung, who now faces a damaging scandal over illegal constructions in a luxury villa that has corroded public trust, an infraction that had earlier torpedoed the chances of his election rival, tycoon Henry Tang.