Tensions continue to simmer after police shot a protester on Monday in some of the worst violence since protests began

The United States condemned what it described as the “unjustified use of deadly force” in Hong Kong after one of the most violent days in nearly six months of protests in the Chinese-ruled city, which remained on edge on Tuesday morning.

Hong Kong police shot and critically wounded a 21-year-old protester on Monday and a man was set on fire in escalating violence that prompted leader Carrie Lam to denounce the demonstrators as “enemies of the people.”

“Hong Kong police and civilians alike have a responsibility to de-escalate and avoid violent confrontations,” an official with the US administration official told Reuters, speaking on condition of anonymity.

In a separate statement, US State Department spokeswoman Morgan Ortagus said the US was watching the situation in Hong Kong with “grave concern” and condemned violence on all sides.

“The United States urges the Hong Kong government to build on its dialogue with the Hong Kong public and begin efforts to address the underlying concerns driving the protests. We also urge the protesters to respond to efforts at dialogue,” she said.

Simmering anger

Tension continued to simmer on Tuesday as protesters blocked roads and junctions for a second day. Riot police were deployed at metro stations, which have been a target of the protesters’ anger.

Riot police fired tear gas on a university campus where students were building barricades.

Al Jazeera’s Divya Gopalan, reporting from Hong Kong said 10 universities had stopped classes.

“Universities now seem to be the focal point of the protests,” she said. “Many students are very angry with the police actions and very angry with the government’s actions. They say that no one’s listening to them.”

Demonstrators turn a goal post into barricade during an anti-government protest at the Chinese University of Hong Kong. [Shannon Stapleton/Reuters]

A water cannon truck was stationed outside government headquarters, where the city’s Executive Council was due to hold its weekly meeting.

Lam said on Tuesday protesters who were trying to “paralyse” the city were extremely selfish and said she hoped all universities and schools would urge their students not to participate in violence.

Protesters are angry about what they see as police brutality and meddling by Beijing in the freedoms guaranteed under the “one country, two systems” formula put in place when the self-governing territory returned to Chinese rule in 1997. The agreement allows Hong Kong wide-ranging freedoms not available on the mainland.

Ortagus urged Beijing to honour commitments that “Hong Kong will ‘enjoy a high degree of autonomy’ and that the people of Hong Kong will enjoy human rights the freedoms of expression and peaceful assembly.”

China denies interfering and has blamed Western countries for stirring up trouble.

More than 260 people were arrested on Monday, police said, bringing the total number to more than 3,000 since the protests escalated in June.