However, education sector lawmaker Ip Kin-yuen said detained teachers have the right to the presumption of innocence.
The government’s request to suspend a ruling that found the ban unconstitutional was denied.
Educators in Richmond are concerned by report of a fight between students and emergence of a letter about Hong Kong’s ‘evil’ protests.
Demonstration is the first to get letter of no objection since mid-August.
Festival Grand cinema will also remain closed, as owners say they need up to five months for repairs.
A letter of no objection has been issued for the event, which will be held two days before the United Nations' annual Human Rights Day.
Pro-protester organiser known only as Steve also stated that donated money remained untouched and that the fair would go on.
After months of anti-government protests, online rumours, allegations and fake news claims are put to the test.
Yuli Riswati has been detained by immigration authorities since November 4, according to a support group working on her behalf.
Ireland, Singapore and Canada are some of the countries that have issued advisories against travelling to Hong Kong for non-essential reasons.