TIMELINE: What happened before, during, after Senate shooting incident

Gunshots rang at the Senate building in the evening of May 13.

Operatives of the National Bureau of Investigation (NBI) and the Office of the Senate Sergeant-at-Arms (OSAA) reportedly fired their guns.

The incident happened as Senator Ronald “Bato” dela Rosa was under the protective custody of the Senate amid the arrest warrant issued by the International Criminal Court (ICC) in connection with the Duterte administration's war on drugs.

Also, the impeachment articles against Vice President Sara Duterte had just been transmitted to the Senate.

This is the timeline of events before, during, and after the incident based on the investigation of the Philippine National Police (PNP):

Before the shooting

May 12

• 10 a.m. — A security coordination meeting was conducted at the OSAA with representatives from the GSIS Security Office and Senate personnel from the Philippine National Police, Bureau of Fire Protection, and Armed Forces of the Philippines.

May 13

• 2:21 p.m. — Government Service Insurance System president and general manager Jose Arnulfo Veloso directed the implementation of red alert status. GSIS security personnel inspected the complex and identified nine vulnerable areas within the compound.
• 3:13 p.m. to 4:07 p.m. — NBI agent Aubren Cosidon and three other NBI agents inspected the identified vulnerable points inside the GSIS compound.
• 5:08 p.m. — GSIS sent a letter request to NBI.
• 5:23 p.m. — Senator Ronald “Bato” dela Rosa appealed to the public for support during an ambush interview at the Senate building. Earlier in the day, he also recited the Philippine Military Academy hymn and sought sympathy from fellow uniformed personnel.
• 5:58 p.m. — The Senate adjourned its session.
• 6:14 p.m. — The Supreme Court did not issue a temporary restraining order on Dela Rosa’s petition.
• 6:17:59 p.m. — Twenty-one NBI agents arrived at the GSIS main building escorted by GSIS security personnel.
• 6:51 p.m. — NBI agents began a security survey and inspection of the nine vulnerable areas identified by GSIS security.
• 6:57 p.m. — Acting Senate Sergeant-at-Arms Major General Mao Aplasca announced that somebody would be arrested but refused to identify the person. He also said the Senate would be placed under total lockdown within five minutes.
• 7:02 p.m. — Two NBI agents were posted at Vulnerable Area 5, identified as the Outdoor Canteen Hallway leading to Kalayaan Garden.
• 7:05 p.m. — The Senate implemented a total lockdown.
• 7:11 p.m. — The House of Representatives formally transmitted the Articles of Impeachment against Vice President Sara Duterte to the Senate.
• 7:17 p.m. — Two NBI agents remained detailed to secure Vulnerable Area 5.
• 7:22 p.m. — House Secretary General Cheloy Garafil and House Sergeant-at-Arms Ferdinand Melchor Dela Cruz completed the transfer of the impeachment articles to the Senate.
• 7:39 p.m. — Coordination was conducted regarding repair works at a door fronting the Senate lower ground floor lobby.

During the shooting

• 7:44 p.m. — Aplasca allegedly assembled Marine security personnel, members of the PNP Police Security and Protection Group, and OSAA security personnel and gave a “lock and load” order.
• 7:45 p.m. — A gunshot was heard inside Senate premises. Aplasca and accompanying personnel were reportedly en route to the target area near the exit door leading to the Outdoor Canteen Hallway and Kalayaan Garden.
• 7:46 p.m. to 7:49 p.m. — A confrontation occurred between OSAA personnel and the two NBI agents posted at the Outdoor Canteen Hallway leading to Kalayaan Garden, based on indoor and outdoor CCTV footage cited in the investigation timeline. Aplasca, Joemil Ledesma, and Charlie Montilla of OSAA were identified in the CCTV.
• 7:50 p.m. — Aplasca and OSAA personnel were seen allegedly abandoning the scene.
• 7:53 p.m. — The targeted NBI agents reportedly conducted evasive maneuvers before linking up with other NBI agents.

After the shooting

• 8:14 p.m. — Senate Secretary Mark Llandro Mendoza said “perceived NBI agents” entered the Senate premises.
• 8:39 p.m. — NBI director Melvin Matibag told reporters that NBI agents were not involved in the shooting.
• 9:35 p.m. — Interior Secretary Jonvic Remulla and Senate President Alan Peter Cayetano held a press conference outside the Senate building.
• 9:36 p.m. — The PNP conducted a clearing operation.

May 14

• 2:30 a.m. — Dela Rosa left the Senate building.

The investigation timeline also cited a possible getaway vehicle allegedly registered to Senator Robin Padilla.

—AOL, GMA News