ANGELES CITY -- Five persons including an American national were killed by a lone robber inside an apartment along Manuela Street at Hensonville Court subdivision in Barangay Malabanias here on Thursday.

Police identified the victims as couples Albert and Jeanette Androneda Mitchell; housemaids Marissa Prado and Isabel Pajardo; and driver Boy Vergara.

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Angeles City Police Director Danilo Bautista said a special investigation task group was formed Friday to track down and arrest the killer.

Bautista added that the task force will be composed of the Criminal Investigation Detection Unit (Cidu)-Central Luzon, Regional Intelligence and Investigation Division (RIID), and Angeles Police Intelligence Division.

Bautista said they have wage a manhunt operation against the suspect who was able to escape shortly before security guard Angelito Prado, husband of Marissa Prado, learned about the incident.

The victims sustained gunshot wounds in the different parts of their body and were already dead when found by Prado.

Bautista said Prado and another unidentified guard earlier held a man who apparently came from the victims' apartment.

The guard reportedly called his wife at the apartment but no one answered the telephone. This prompted him to proceed to the apartment where he discovered the victims who were already dead.

Bautista said the guard hurriedly went back to the guard house but the suspect was no longer around.

The unidentified guard told police that the suspect asked permission to load his cellphone but never came back.

The guard said the suspect, who was wearing white shirt, about five feet and six inches in height, white complexion and in his early 30s, boarded a motorized tricycle.

Bautista said robbery could be the possible motive of the suspect as Mitchell's jewelry and cash were missing.

Responding police recovered 13 bullet shells that of a .9mm caliber pistol at the crime scene.

"Maaaring kilala ng mga biktima yung suspek," Bautista said. (Reynaldo G. Navales/With reports of Ric Sapnu)