A Hong Kong secondary school principal filmed swearing at security guards during a student trip to Singapore has resigned, days after being suspended from the position.Lee Cheuk‑hing tendered his resignation on Thursday as principal of San Wui Commercial Society Secondary School in Tuen Mun, school manager Edmund Wong Chun‑sek confirmed.Wong, a former lawmaker, said the school’s board of directors would have to meet to decide whether to accept the resignation, given the many factors involved.01:22Singapore investigates Hong Kong school principal for swearing at security guardsLee’s confrontation with security guards over a parking dispute during the school trip in Singapore last Friday was captured on video and widely circulated on social media, sparking heated discussion in both cities.Footage shows a security guard telling Lee, who is standing in the doorway of a coach, to move the vehicle, but he becomes irate and rudely rebuffs her instructions.“Shut up,” Lee is heard telling her before swearing at her in Cantonese.When another guard intervenes, Lee turns to her and shouts: “You shut up!”