Protests paralyze Hong Kong: What you need to know

Authorities say hundreds of student protesters have been arrested at Hong Kong Polytechnic University, but about 100 were defying police orders to surrender as the standoff entered a third day on Tuesday, AP reports.

The latest: The city's leader Carrie Lam said 600 demonstrators had left the campus, including 200 who are younger than 18, AP notes. Dozens of activists escaped from the building by "shimmying down plastic hosing from a bridge and fleeing on waiting motorbikes as the police fired projectiles," per Reuters.

• Police told protesters to put down their weapons and surrender or face a bombardment of tear gas and rubber bullets, the New York Times reports.
• "At least" 116 people were wounded in the campus clashes, medical officials said, per the NYT.

What they're saying: Police threatened to use live bullets against dissidents on Sunday, after protesters shot arrows and threw petrol bombs at them outside the university. The police said an officer was shot in the leg with an arrow.

Why it matters: The past week has seen some of the bloodiest clashes between police and protesters since the massive pro-democracy demonstrations began in June. Schools "have become a driver of the city's uprising against China's ruling party," the Wall Street Journal notes.

• More than a third of the 4,000 protesters arrested are ages 21 and younger, per police records, the youngest of whom is 11, per the WSJ.
• Beijing blames the school system for failing to impart a strong sense of Chinese national identity to Hong Kong’s young people. It's written new new education guidelines with "the goal to build a stronger national identity for students in Hong Kong and Macau," WSJ notes.
• More than 390 high schools, about 80% of which are secondary schools, established “concern groups” to organize protests. Educators fear a curriculum push for Communist Party ideology could be re-upped in classrooms, per WSJ.

The big picture: Five months of unrest intensified during rush hour last Monday morning when police opened fire on protesters, injuring a 21-year-old man. There have been daily daily demonstrations lasting from the morning into the night since then.

• Chinese army troops stationed in the semiautonomous territory cleared streets on Saturday, which protesters clogged with debris to slow down police. An official said the Chinese army operation was a "voluntary community activity," per Reuters.
• The protest focus has since shifted to the university.
• Students threw petrol bombs to stop police from storming the campus over the weekend, per the Times.

Background: Authorities hoped the October withdrawal of an extradition bill that triggered the city's protests would quell the unrest.

• However, protesters are concerned China may suppress the high degree of autonomy they've enjoyed since the former British colony was returned to the country in 1997.

Go deeper:

• China: Hong Kong courts don't have the power to rule on mask ban
• Violence in Hong Kong as leader denounces "enemies of the people"

Editor's note: This article has been updated with new details throughout.