Don't be silly .... This is NOT a new term .... This slang has been around for over 20-30 years ... just not popular in HK until now
Po-po, Popo, Popos, PoPoA street term for police. Originally from Southern California, where bicycle police, beginning in the 1980s, wore T-shirts marked with 'PO', for 'police officer', in block letters.[citation needed] As these officers rode in pairs, their shirts would read 'POPO' when side by side. from Wikipedia