Ms Lam urged the remaining demonstrators to lay down their makeshift weapons and give themselves up for arrest peacefully, suggesting it was the only route out of the situation.
Around 600 protesters left the Hong Kong Polytechnic University campus on Monday, she said, and 400 were arrested. The other 200 were under the age of 18 and, though not immediately arrested, could face charges in the future.
The university clashes have been some of the most brutal in Hong Kong’s months-long crisis. Protesters occupied it and other campuses last week before police advanced in large numbers on Sunday, triggering a three-day siege that raised fears of the prospect live ammunition would be used.
Footage from the scene showed protesters attempting to flee in large numbers to avoid arrest, with some using rope ladders to abseil down from a footbridge to waiting motorbikes below. It was unclear if any made it out without getting caught.
Speaking to reporters after a weekly meeting with advisers on Tuesday, Ms Lam said: “We will use whatever means to continue to persuade and arrange for these remaining protesters to leave the campus as soon as possible so that this whole operation could end in a peaceful manner.”
Ms Lam was also asked about the appearance of Chinese soldiers on the streets of Hong Kong over the weekend, when hundreds of troops left their barracks in the city to help clean up debris left by protesters.
Analysts called it a show of force from Beijing, while pro-democracy groups called the intervention – which was not formally requested by the Hong Kong government – a breach of the city’s laws.
Asked whether she would seek help from Chinese troops based in Hong Kong, Ms Lam insisted her government remains confident it is able to cope with the situation.
China expressed frustration on Tuesday at a decision by the Hong Kong high court to strike down Ms Lam’s ban on face masks for protesters, which was pushed through using colonial-era emergency regulations.
The court had ruled that the ban went too far in restricting citizens’ rights, and was therefore unconstitutional.
Only China’s parliament had the authority to rule on constitutional matters in Hong Kong, claimed parliamentary spokesperson Zang Tiewei. “No other institution has the right to make judgments or decisions,” he said.
The ban on face masks, imposed at the start of October, has been largely ignored.