(Updates include statements from Caloocan police chief Senior Supt. Chito Bersaluna)

Metro Manila (CNN Philippines, August 18) — A 17-year-old student was killed in an alleged anti-illegal drugs operation in Caloocan City, police said.

The police report obtained Friday said the Grade 11 student, Kian Loyd Delos Santos fired first, which prompted the police to fire back. But accounts from witnesses and a CCTV footage show otherwise.

Police Officer 3 Arnel Oares and 10 other officers were conducting a "one-time big-time operation" in Barangay 160 in Caloocan City late Wednesday when Delos Santos noticed them, the report said.

The minor then drew his firearm and "directly shot" at the police, which prompted Oares to fire back, and kill the student, it added.

The police report said Oares fired "to prevent and repel the unlawful aggression as their lives were in imminent danger."

Two small sachets of suspected shabu, one .45 caliber gun, and four fired cartridge cases were recovered at the scene of the encounter.

Delos Santos was among 12 alleged suspects killed in simultaneous police operations in Caloocan City.

Caloocan City Police Chief Senior Supt. Chito Bersaluna told CNN Philippines' News Night that Delos Santos was not included in its list of suspected drug personalities, but he was tagged as a drug runner "based on a statement of another arrested drug suspect."

CCTV footage from barangay officials seemed to depict a different scenario.

The CCTV footage showed that at 8:24 p.m. Wednesday, a young man believed to be Delos Santos, is being dragged away by two men in civilian clothes, while some young men playing basketball are seen watching the incident unfold.

At 8:57 p.m., two policemen in civilian clothes, arrived at the Barangay Hall to report the supposed shootout. One of the policemen was identified as Caloocan Police Community Precinct Commander Chief Inspector Amor Cerillo.

At the site of the encounter, Delos Santos was found in fetal position with a gunshot wound to his head.

Delos Santos's uncle, Randy, insists that if Kian was really armed, the police should have seen it right away as his nephew was wearing loose boxers.

"Naka-boxer shorts lang 'yan. .45 maisusukbit mo sa boxer shorts? Maging makatotohanan lang tayo," he said.

[Translation: He was wearing boxer shorts. Can you put a .45 caliber in boxer shorts? Let us remain truthful.]

Delos Santos's mother Lorenza, an overseas Filipino worker who flew in from the Middle East on Thursday, demands justice for her son.

Three Caloocan police officers and a precinct commander were relieved for the death of Delos Santos, National Capital Regional Police Office (NCRPO) Director Oscar Albayalde said Friday.

Chief Inspector Cerillo, PO3 Oares, PO1 Jeremias Pereda, and PO1 Jerwin Cruz have been relieved from their posts pending investigation of the case.

Personnel from the National Police Commission and PNP Internal Affairs Office visited the site of the encounter on Friday.

Caloocan Police Chief Bersaluna said the four policemen were relieved "to give way to the investigation."

"As part of the PNP standard operating procedure, they are administratively relieved from their post so they could not influence" the investigation, he said in the interview with CNN Philippines.

He added that Cerillo was the team leader of the precinct's drug enforcement unit. The unit also included the three other policemen who were removed from their posts.

The policemen are allowed to wear civilian clothes, instead of their official police uniform during an operation.

"'Yung drug enforcement unit, they can wear civilian attires, especially when conducting anti-illegal drugs operations," Bersaluna said.

Caloocan police

The death toll of "legitimate" anti-crime and anti-drug synchronized operations is at 69, the biggest toll of deaths in one week in recent months.

Read: 32 dead, 107 arrested in Bulacan drug sweep

Read more: 14 suspected drug pushers killed in one-night police anti-crime drive in Manila

The deaths have triggered an outcry Friday from lawmakers and human rights groups. The Senate plans to call for an investigation into the rash of killings.

Duterte administration defends cops

Philippine National Police Chief Director General Ronald Dela Rosa on Friday once again defended his men, saying the hundreds of persons arrested from the operations in Bulacan, Manila, and Caloocan prove the police do not kill suspects unless they pose as threats.

He said the increase in number of drug-related casualties is just a result of the police's intensified effort to fight the drug problem.

"Kaya nga nag-one-time big-time operation, bigtime results. Malawakan, maramihan. Maraming targets, simultaneous, sabay-sabay na ginawa, kaya sabay-sabay din ang resulta. Sabay-sabay din naglabasan yung numero na napakataas na maraming namatay dahil sabay-sabay din sila nakipaglaban," he said.

Dela Rosa said the PNP will continue their fight against illegal drugs despite criticism.

"Ang instruction ni Pangulo is very clear naman: Continue the war on drugs. Wala siyang specific instruction na "pumatay kayo ng marami." Ako rin walang instruction sa mga pulis na "mas maraming mamatay mas masaya ako." Ang instruction ko sa kanila is paigtingin yung kampanya ninyo sa droga," he said.

Related: PNP Chief: 'One-time, big-time' anti-crime operations to continue

Presidential Spokesperson Ernesto Abella believes the death of De los Santos is an "isolated" case.

President Duterte has repeatedly assured the military and police they will be spared from legal consequences as long as they observe their mission.