Clashes between Hong Kong police and protesters escalated on Monday, as police stormed the Hong Kong Polytechnic University campus.Police faced off against protesters near the campus over the weekend and fired tear gas and water cannons filled with blue dye which stains clothes and irritates the skin. Protesters then barricaded themselves in the university and responded by firing molotov cocktails and other makeshift weapons at police.By Monday morning, protesters appeared to leave the university en masse amid threats from police to use live rounds and other forceful dispersal methods.Visit Insider's homepage for more stories.Clashes between Hong Kong police and protesters escalated on Monday, as police stormed a university campus that had been occupied by protesters over the weekend.Hong Kong Polytechnic University, located in Hung Hom, became a battleground for pro-democracy protesters against riot police as demonstrations enter into their sixth month and have seen a major uptick in violence in recent weeks.Police faced off against protesters near the campus over the weekend and fired tear gas and water cannons filled with blue dye which stains clothes and irritates the skin. Protesters then barricaded themselves in the university and responded by firing molotov cocktails and other makeshift weapons.According to The Washington Post, protesters have accumulated a range of weapons to combat police, including javelins and bows and arrows that were likely taken from the university's athletic department.In a statement, university authorities said they were "gravely concerned that the spiraling radical illicit activities will cause not only a tremendous safety threat on campus, but also class suspension over an indefinite period of time."Police on Sunday evening threatened to arrest protesters for rioting, an offense which carries up to 10 years in prison. By Monday morning, police stormed the campus and threatened to use live rounds if protesters did not "stop assaulting the police using cars, gas bombs and bows and arrows."By Monday morning, video appeared to show protesters leaving the campus en masse.Now accompanying this mass exodus of people, no comment now on their actions, need to keep their plans safe pic.twitter.com/WQfMRLcPfH' Joel Christian (@2legit2trip) November 17, 2019Last week, black-clad protestersoccupied the Chinese University of Hong Kong near Tai Po for days and clashed with police, hurling bricks and building massive bonfires to prevent authorities from entering the campus. On Tuesday, police said they were working towards reaching a "peaceful solution" but the situation on the ground "[continued] to intensify.""Such violence has reached a deadly level, posing a serious threat to Police officers and everyone at scene. The rioters threw hard objects and petrol bombs onto Tolo Highway, endangering road users' safety. The rioters also hampered emergency services including ambulance services," Hong Kong Police Force said in a statement.Police responded with tear gas and rubber bullets.Last week saw a major increase in violent responses from both protesters and police. On Monday, police officers fired live rounds at protesters at point-blank range, injuring one man. On Tuesday, police appeared to pepper-spray a woman directly in the face during a tense standoff near Hong Kong Polytechnic University.A 57-year-old man on Monday was set on fire during a disagreement with protesters in Ma On Shan. On Wednesday, police say a 70-year-old pedestrian sustained head injuries and later died after being hit in the head with a brick in Sheung Shui. On Sunday morning, police say an officer was injured in the leg after a protester fired off a bow and arrow nearThe Hong Kong Polytechnic University.Here are 13 striking photos which show how Monday's violence unfolded.The Hong Kong Polytechnic University became the scene of chaos on Sunday.Clashes first took place on the roads and highways near the university before protesters occupied the campus.Protesters confronted police using a number of makeshift weapons including slingshots, molotov cocktails, and bows and arrows.Police surrounded the university.And fired tear gas to disperse crowds.Police also sprayed protesters with water cannons colored with blue dye.Protesters responded by attacking police using bows and arrows.Protesters also hurled molotov cocktails.And hid behind makeshift barricades.And burned fires across the campus.Protesters appealed for foreign intervention during the all-night standoff.Fiery explosions could be seen inside the campus as riot officers entered before dawn on Monday morning.The smoke from the fire billowed out into the morning sky. Click here to read full news..