"We could not tolerate the small group of people who used the opportunity … to express their personal dissatisfaction with our police force," he said.

In a rare move, he also announced he had ordered the education chief to submit a report on the Lam case.

Leung said: "I stress that the police force who carried out their duty to defend public order was fair, neutral, unbiased and acting in accordance with the law.

"As we can see on internet videos, there were protesters there who provoked the police in different ways … The Hong Kong police exercised forbearance, while enforcing the law."

Leung reiterated that former Executive Council members Franklin Lam Fan-keung and Barry Cheung Chun-yuen deserved apologies from the people that reported them to the Independent Commission Against Corruption over possible conflicts of interest.

Lam, who was accused of profiting from inside information by selling two flats ahead of the introduction of new stamp duties, resigned this month, hours after the Department of Justice said it had insufficient evidence to prosecute him.

The ICAC also said it would not follow up on the Cheung case without further evidence.

He quit all his public posts in May when his failed Hong Kong Mercantile Exchange came under criminal investigation, which is ongoing.

Leung said: "After the ICAC cleared Lam, not one person - including those who reported him or the political parties who stirred up the incident - said sorry to Lam, publicly or privately.

"The people who reported Cheung, too, did not apologise to him."

Leung stressed that the ICAC should not be used as "a political tool" and pointed out the government had now reviewed its conflict-of-interest guidelines for ministers.

The Democratic Party's chief executive, Lam Cheuk-ting, a former anti-graft investigator, said Leung's call to apologise was an "outrageous joke".

He said that the chief executive should not put pressure on ICAC or deter the public from reporting any suspicious case to the graft-buster.