Hong Kong protests escalated early Monday as pro-democracy protesters clashed with police officers in an attempt to surround government headquarters.

The city's Chief Executive Leung Chun-Ying condemned protesters for the clash and over two months of protests calling them "violent radicals."

"Many residents are of the view that there is a limit to their tolerance," Leung told the South China Morning Post, referring to residence who are losing patience with protesters.

Hong Kong protesters are continuing their fight for democratic reform, camping out on the city's streets and voicing their views against the Chinese government.

Police used pepper spray, batons and riot shields as they tried to clear the streets filled with protesters. Many of them carried yellow umbrellas, a new symbol of the pro-democracy movement.

Joshua Wong, a Hong Kong pro-democracy protest leader, continued a hunger strike Tuesday saying that it is the only way for the government to listen to them.

"I know it is really harmful to my body, however it is the only way to give pressure to the government to get a meeting with us," Wong told CNN.

The 18-year-old leader of the Scholarism group started the hunger strike amidst clashes with police late Monday with two other groups.

"If the government can have a proper meeting with Scholarism to discuss whether political reform will be launched immediately, we will stop the hunger strike," Wong said.

Photos released on social media showed at least one police officer being taken away on a stretcher and protesters with bruises from police attacks. Police Senior Superintendent Tsui Wai Hung said 40 protesters had been arrested. 

Since protests started in September a little over 500 people were sent to accident and emergency wards. Yesterday's clash resulted in 40 people being hospitalized.

"The action was aimed at paralyzing the government's operation," Alex Chow, secretary general of the Hong Kong Federation of Students and another key organizer of the movement told USA Today.

The start of the protest drew over 100,000 supporters.