Gunshots were heard at the Senate Wednesday evening as the upper chamber was on lockdown.

On Thursday, Malacañang said Senate Sergeant-at-Arms and retired Police Major General Mao Aplasca fired the the first warning shot. Interior Secretary Jonvic Remulla said that Office of the Sergeant-at-Arms (OSAA) personnel fired 27 shots while a National Bureau of Investigation (NBI) agent fired five shots.

Aplasca said the OSAA personnel issued a verbal warning first before firing a gun.

But when are warning shots allowed?

Philippines National Police (PNP) spokesperson Police Brigadier General Randulf Tuaño told GMA News Online that the guidelines for warning shots are included in the Revised PNP Operational Procedures.