MANILA - Philippine National Police (PNP) chief Gen. Archie Gamboa on Wednesday ordered an investigation into the birthday celebration of the Metro Manila police chief while stringent community quarantine measures against the spread of the COVID-19 are in place for the entire region and in some parts of the country.

Gamboa earlier defended Major Gen. Debold Sinas over recent his birthday celebration, which drew backlash for supposedly violating physical distancing and mass gathering guidelines.

• 'I don't think na merong violation': PNP chief defends Sinas' birthday fête

The PNP-Internal Affairs Service was instructed to send a team to the National Capital Region Police Office "to initiate a formal inquiry into the incident," the police's public information office said in a statement.

"The PNP is not exempt from strict rules on mass gathering and I am directing all unit commanders to prohibit any and all social gatherings," the statement quoted Gamboa as saying.

"The Chief PNP strongly reiterates strict observance of all public health protocols and biosafety standards by all personnel at all times," it added.

Interior Secretary Eduardo Año, whose agency governs over the PNP, disapproved of the party.

• Police official's lockdown party a 'big no-no': DILG

"That's a big no-no," he told ABS-CBN's Teleradyo.

"Ang aking sinasabi sa ating mga government official, lalo na sa nasasakupan ng DILG, iyong tinatawag nating delicadeza. May mga pagkakataon na kailangan maging example ka," he said.

(I remind government officials, especially those under DILG, of the so-called delicadeza or sense of propriety. There are instances in which you should set an example.)

Photos shared by the Metro Manila police office on Facebook showed police officers giving Sinas roses and bumping fists with him during the May 8 event.

The official was also photographed mingling at a table, while others lined up at buffet meals. Some of the photos in the post have been deleted.