A Hong Kong school that instantly dismissed its principal after he was filmed swearing at security guards in Singapore has published an advertisement to recruit a new head, requiring applicants to have “excellent character”.

The advertisement was posted on the school’s website on Tuesday morning, six days after its governing board decided to terminate principal Lee Cheuk-hing with immediate effect, saying his continued presence would “gravely disrupt the operation of the school and prevent teachers and students from moving forward as soon as possible”.

Lee was filmed swearing at security guards during a school trip to Singapore on May 22, prompting his suspension and an investigation by the Education Bureau.

The footage shows the guards telling Lee, who is standing in the doorway of a coach, to move the vehicle, but the principal rebuffs their instructions telling them to “shut up”.

After apologising over the incident, Lee said he would resign on May 28 and requested his last day be August 31. But the school board invoked a clause under the Employment Ordinance allowing summary dismissal without notice or payment in lieu under certain conditions.

The board earlier said that Lee’s “vulgar” behaviour during the exchange tour violated the professional code of conduct for teaching staff, particularly guidelines set by the bureau.