BEIJING, September 29. /ITAR-TASS/. A popular photo sharing network Instagram has been partially blocked in mainland China amid pro-democracy protests that have swept Hong Kong over the past several days.

Since late Sunday, users have been unable to access Instagram that has recently shown images of chaotic scenes as police fired tear gas at demonstrators. The clashes have left more than 40 people injured.

On Sunday, thousands of protesters, calling for the democratization of the election system in China’s special administrative region, blocked the central streets of Hong Kong.

The protests are part of a campaign of civil disobedience called "Occupy Central with Peace and Love" aimed at paralyzing the key business area and push Hong Kong and mainland China to revise their election plans.

The unrest comes in response to a move last month by the Chinese authorities to announce that candidates for the 2017 chief executive election in Hong Kong would first have to be approved by a nominating committee.

Protesters say that the proposal will allow Beijing to control the selection of candidates at the nomination stage, stressing that this undermines the people's right to freely choose their leader.