Protests in Hong Kong during Hu's visit

• President Hu Jintao is in the territory for a three-day visit
• Hong Kong has prospered since Britain handed it over to China in 1997
• However, some Hong Kong residents are concerned about Beijing's intentions
• He will mark the handover's anniversary but also be the focus of protests

Hong Kong (CNN) -- Hong Kong protesters took to the streets Sunday as Chinese President Hu Jintao visited the former British colony to mark the 15th anniversary of its return to Beijing rule.

Hu also attended the inauguration of the Hong Kong chief executive amid growing discontent toward Beijing over its human rights records, among others.

Small planes flew overhead with flags of China and Hong Kong during the ceremony.

Protesters criticized last month's death of Li Wangyang, a high-profile dissident who spent decades in prison for his support of the Tiananmen Square student rallies in 1989.

Hong Kong has prospered since its last British governor, Chris Patten, bade the territory a tearful farewell on July 1, 1997.

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The Chinese territory has benefited from its position as a financial and commercial gateway, riding the mainland's spectacular economic boom of the past two decades.

But the economic rewards are mixed with unease about Beijing's intentions for Hong Kong in the long term, including concerns about possible threats to freedom of speech and the rule of law.

Some Hong Kong residents have expressed reservations about the effect mainland Chinese residents have on property prices and public services in the city.

Nonetheless, Hong Kong has its own borders and immigration control even with China. It has its own currency, its own police force and system of law courts. It also enjoys a freedom of expression and demonstration to a degree unheard on the mainland.

The Chinese president is scheduled to attend a string of other events over the next three days, including a fireworks display and a parachute jump by members of the Chinese People's Liberation Army.

Hu also attended the inauguration of chief executive of Hong Kong, Leung Chun-ying, the Beijing-backed leader who took office Sunday.

In addition to human rights issues and Li's death, protesters have demanded greater democracy and called for Beijing to stop intervening in local affairs.

Li was found hanging in his hospital room in Hunan province on June 6. Local authorities said he had committed suicide, but friends of the deaf and blind labor rights activist have denied the claim.

Hong Kong government officials have also questioned whether Li committed suicide.

CNN's Jethro Mullen, Tim Schwarz and Hilary Whiteman contributed to this report.