Spontaneous protests broke out at several locations in Hong Kong Friday afternoon after the death in hospital of a student.

Chow Tsz-lok, also known as Alex Chow, 22, was found with serious head injuries five days ago, in a car park near the scene of a street battle between police and anti-government demonstrators, and had been in a coma since.

Police earlier told reporters that Chow fell from the third to the second story of the car park. Officers were in the car park at the time, but the police deny that Chow was pushed or that they were pursuing him.

Although the circumstances remain unclear, the computer science undergraduate is nonetheless being regarded by protesters as having died as a result of injuries sustained during a demonstration—potentially the first such case in five months of increasingly violent unrest.

Within hours of his death on Friday morning, crowds of office workers began gathering in the financial district, occupying main thoroughfares and chanting “Hongkongers, take revenge!” Calls for protesters to take “blood for blood” circulated online.

Hundreds also rallied in different parts of the Kowloon peninsula and at the Hong Kong University of Science of and Technology (HKUST), where Chow was a student.

According to local media, HKUST’s president, Wei Shyy, cut short a graduation ceremony Friday in order to visit Chow’s family at hospital, and announced Chow’s passing to the graduands present.

Hundreds of students later marched on his campus residence to demand he condemn alleged police brutality. Live news images showed his lodge heavily graffitied and windows broken. A canteen and a cafe were also reportedly ransacked and vandalized. The university urged students to “exercise restraint during this difficult moment.”

Speaking at a vigil on campus, Rey, a 19-year-old business student, said: “The situation has really crossed a moral line. This is not really about opposing political stances anymore. The police’s use of excessive force has resulted in a tragedy, and there is no way we can accept this.”

Reverend Chu Yiu-ming, a founder of the 2014 Occupy Central movement, addressed the vigil at HKUST saying that Chow “used his life to safeguard freedom. Even though his life on this planet has been cut short, yet his light is shining on us, inspiring and encouraging us.”

Thousands also gathered at the suburban car park where Chow was found unconscious. Mourners, including many families with young children, lit candles, laid floral tributes and wrote messages of condolence.

A salesman named Siu, who said he was in his 50s and lived opposite the car park, said: “I was heartbroken when I learned he had lost his life. He’s just a teenager. I don’t think the government is going to respond to this situation in a satisfactory manner. What they really need to do is face the reality and reflect on why the society has come to this—not stay in their own parallel universe.”

Live news feeds showed impromptu vigils taking place in several other districts of Hong Kong. Shortly after 8:00 p.m., a tense standoff took place in the Causeway Bay retail and entertainment district between riot police and angry crowds who occupied key intersections, shouting slogans and abuse.

Protesters also began setting up barricades on Nathan Road—the main artery through the congested Kowloon peninsula—and in at least two northern suburbs. A major suburban train station was evacuated after protesters began smashing the facilities.

Hong Kong’s embattled administration meanwhile issued a statement expressing “great sorrow and regret” over Chow’s death, and extended sympathies to his family. It added that a police crime unit was investigating the case. Some legislators also held a minute’s silence for Chow.

The young man’s demise comes at a time of worsening political tensions in Hong Kong and is sure to galvanize anti-government protesters, who are demanding greater political freedom for the enclave—a British colony for 156 years before it was retroceded to China in 1997.

Two days ago, a conservative politician was stabbed and hospitalized while out campaigning in local elections. Three days before that, a pro-democracy district councilor was attacked and had part of his ear bitten off after a political row outside a shopping mall. In recent weeks, at least two other democracy campaigners have been attacked and hospitalized, and two teenagers shot by police with live rounds, both of whom survived.

Thousands have been injured and arrested since the protests began in June. The unrest has taken an especially heavy toll on Hong Kong’s vital tourism and retail industries, pushing the territory into recession.

—With reporting by Abhishyant Kidangoor and Hillary Leung/Hong Kong

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