HONG KONG (AGENCE FRANCE-PRESSE/XINHUA) - A prominent Hong Kong democracy activist on Wednesday (July 29) vowed to appeal his sacking by a top university as city leaders and education chiefs were accused of failing to defend academic freedoms under Beijing's tightening grip.

Law professor Benny Tai, 56, said he was sacked on Tuesday by a disciplinary committee at the University of Hong Kong (HKU) after he was jailed last year for taking part in pro-democracy protests.

In a Facebook post on Wednesday, Prof Tai said he would appeal the university's decision and consider launching a judicial review.

He also made a personal appeal to city leader Carrie Lam, a pro-Beijing appointee.

"Though I know this is a futile process, Carrie Lam cannot evade...her responsibility of infringing Hong Kong's academic freedom," Prof Tai wrote.

"There is clear evidence that a power beyond the University has overturned the decision of the University," he said, a reference to Beijing.

Prof Tai is a leading figure within Hong Kong's pro-democracy movement.

A staunch non-violence advocate, he was jailed last year over his involvement in huge pro-democracy protests in 2014 that brought parts of the city to a standstill for weeks.

He is often the target of vitriolic statements from China's government.

State media has previously described him as a "hardcore troublemaker" colluding with foreign forces.

The Liaison Office, which represents Beijing's government in the semi-autonomous city, released a statement late Tuesday expressing support for the dismissal.

The decision helps restore normal teaching order and a sound campus environment and shows that the university shoulders the responsibility to the entire society, a spokesman of the office said in a statement.

Earlier in the month, the same office accused Prof Tai of trying to foment a revolution.

In an email to AFP, a University of Hong Kong spokesperson said the institution was "committed to upholding and safeguarding academic freedom".

"The university respects the freedom of university members in expressing their views, yet we believe freedom should come with responsibilities and should be exercised within the law," it said.

The sacking has sent a new chill through the semi-autonomous city's campuses already rattled by Beijing imposition of a sweeping national security law last month that has begun to criminalise certain political views.

"Benny Tai has become a martyr to civil disobedience," a political science professor at HKU wrote on his Facebook page.

"The University of Hong Kong has sacrificed its reputation and it will not be able to hold its head high in the international academic community," he added. "This day will become a major stain in the history of the University of Hong Kong that cannot be washed away."

Ms Sophie Richardson, a China expert with Human Rights Watch, said international universities should now reassess their relationship with HKU.

"Calling all unis with ties to @HKU and claim to uphold #academicfreedom: time to speak up about this outrage," she tweeted.

Joshua Wong, a prominent student activist who has also served jail time for leading protests wrote: "#Beijing now extends its reach to academic freedoms in #HK."

Late Tuesday, the university released a statement saying it had "resolved a personnel issue concerning a teaching staff member" but it did not name Prof Tai or give any details on what the outcome was citing privacy.

Hong Kong has some of Asia's best universities, aided by free-speech protections denied on the authoritarian mainland.

But Beijing has made no secret of its desire to overhaul schools and universities which it believes were partly responsible for the huge and often violent democracy protests that broke out last year.

China has called for more patriotic education, and the new security law has already prompted schools and libraries to pull some books.

Pro-Beijing figures have called for cameras in classrooms to monitor teachers.

Earlier this month AFP obtained an email to staff from an administrator at one HKU faculty warning there would be "zero-tolerance against politics or personal political views brought into classrooms".

HKU said the email was private correspondence and did not constitute official policy.