China rotated troops in its People's Liberation Army garrison in Hong Kong on Thursday, days before protesters planned to hold a march calling for full democracy for the Chinese-ruled city after three months of sometimes violent demonstrations.

China's military will make even greater "new" contributions to maintaining Hong Kong's prosperity and stability, state news agency Xinhua cited the People's Liberation Army garrison in the territory as saying.

Observers estimate the Hong Kong garrison numbers between 8,000 and 10,000 troops split between bases in southern China and a network of former British army barracks in Hong Kong.