MANILA, Philippines – An American Air Force retiree and four Filipinos were found shot to death Thursday inside their home north of Manila during an apparent robbery, police said.

City police chief Danilo Bautista said the bodies of Albert Mitchell, his wife, and three others were found with gunshot wounds inside Mitchell’s home in a subdivision in Angeles city, near the former U.S.-run Clark Air Force Base some 80 kilometers (50 miles) northwest of Manila. The victims’ faces were covered with cloth.

The other victims were two maids and an unidentified man, all Filipinos. Mitchell’s age and hometown were not immediately available.

Bautista said a manhunt was being conducted for a lone assailant who fled after a suspicious security guard accosted him at the subdivision gate.

The guard asked a co-worker to hold the suspect while he checked on Mitchell’s home, but the man was able to escape on a motorized rickshaw, leaving behind a sack with items apparently stolen from Mitchell’s home, including a DVD player and computer accessories. He said police were still verifying what other items were stolen from the house.

Slugs from a 9mm pistol were found at the crime scene.