The Education Department is investigating up to 40 private schools suspected of publishing misleading advertisements or running unregistered courses.
The move deepens the controversy over private schools' operations, and comes as part of a government crackdown which has already seen one school closed. Tutelage Education Centre in Wellington Street, Central is now facing possible legal action for allegedly placing false or misleading adverts about unapproved programmes.
Tutelage has pledged to refund money to up to 1,000 students affected.
Other schools under investigation include Xue Cui College for allegedly running advertisements about three unapproved courses and Welkin Computer Training Centre for admitting students for unregistered courses.
Senior education officer Karina Wu Wong Kit-wai said the department would take legal action against the schools if necessary.
Hong Kong has about 1,300 such private tutorial schools, classified as other schools, offering short courses in subjects including languages, computers and management.
While not willing to name all the schools under investigation, Ms Wu said the department had stepped up efforts to stamp out bogus courses and advertising.
She said that student complaints about such practices had mounted during the past year and led to the education department tightening its laws in June.
The education ordinance states that it is an offence to offer unregistered courses, with possible fines of $50,000 if convicted. It was altered in June to state that advertising must not be misleading, and fines on conviction had been increased from $25,000 to $100,000, Ms Wu said.
'After we amended the law we have been keeping up close monitoring of the institutions that put adverts in newspapers. We are looking at the schools and will take prosecution action if necessary,' she said.
She said the department was investigating whether the schools were offering misleading advertisements or were running courses that were themselves unregistered or held in unregistered school premises.
Ms Wu warned students to look carefully at advertisements and to avoid paying up-front fees - which ranged from $2,000 to $10,000 - because there was a risk they could lose their money.
They should be particularly wary of operators that offered discounted rates in exchange for up-front payment. Fees should be paid in installments, she said.
Before enrolling, students should ensure that prospective schools had certificates of registration and fees certificates - listing Education Department approved courses and the amount of approved fee installments the school can collect.
'We introduced the law because we found that more institutes have been violating the ordinance over the past year,' Ms Wu said. 'We are always calling on students to look carefully before they enrol for any new course and check the registration for schools.'
The department deregistered one group of schools last month - Infonet College - because it was collecting fees and enrolling students for unregistered courses.