By James Pomfret
HONG KONG (Reuters) - Thousands of students braved sweltering heat in Hong Kong on Monday to demand greater democracy as they launched a week-long boycott of classes, underscoring a restive younger generation's determination to challenge the Chinese Communist Party.
Wearing yellow ribbons, students from more than 20 universities and colleges packed into the grounds of picturesque, bay-side Chinese University where they were greeted by banners that said: "The boycott must happen. Disobey and grasp your destiny."
The former British colony returned to Chinese rule in 1997 with a high degree of autonomy, but Beijing last month rejected demands for people to freely choose the city's next leader, prompting threats from activists to shut down the Central finance district as part of their pro-democracy campaign.
"We demand the government responds to our call to endorse civil nominations," said Alex Chow, leader of the Hong Kong Federation of Students, one of the organizers of the boycott who also called on Hong Kong to "reject fake elections".
Some of the student leaders wore black T-shirts with the words "democracy now".
Students converged on a long boulevard at the university, with some carrying umbrellas to protect them from the baking sun, and many chanting "united we stand" and "democracy now".
Leading academics in Hong Kong have voiced support for the boycott, with some offering to record lectures and post them online for students who miss school to watch later.
"As long as the spirit of democracy stays alive, we cannot and will not be defeated," said Chan Kin-man, a co-founder of the Occupy Central movement that has threatened to blockade the heart of the Asian financial center to demand full democracy.
Managing Hong Kong is proving a challenge for Beijing, which is worried that calls for democracy in Hong Kong and the nearby former Portuguese colony of Macau could spread to cities on the mainland, threatening the Communist Party's grip on power.
"I believe on August 31, when the National People's Congress made their decision, it crushed the dreams of some Hong Kong people who have been fighting hard for democracy for the past 30 years," said third-year student Hong Yuen, referring to Beijing's decision to rule out full democracy.
Hong Kong has been dogged by a series of rallies this summer over the issue of electoral reform, underscoring the difficulties Beijing faces in shaping its vision for the city's political future.
The class boycott coincides with a trip to Beijing by some of Hong Kong's most powerful tycoons where they are expected to discuss Hong Kong politics with Chinese leader Xi Jinping.
A survey by the Chinese University showed more than a fifth of Hong Kong residents are considering leaving the city, spurred by concerns over its political future.
(Reporting by Venus Wu and Diana Chan; Writing by Anne Marie Roantree; Editing by Nick Macfie)