Police in Olongapo, the Philippines, filed charges Monday against six Filipinos, including a policeman and a navy sailor, in connection with last month's slaying of a U.S. Marine sergeant from Orange County.
Police had announced Saturday that of two of the six suspects had signed documents confessing to the May 4 killing of Gunnery Sgt. John Fredette of Buena Park.
The charges of attempted robbery with homicide and illegal possession of firearm carry a maximum penalty of 30 years in jail, said assistant prosecutor Nini Alcala.
Alcala said she would schedule a preliminary investigation soon to determine if the case warranted formal trial before a civilian criminal court. Prosecutors declined to speculate on the motive for the killing.
The principal suspects were identified by police as Wilfredo Corpus, 20, and Rosauro Otian, 25. In the course of the police investigation, the two confessed to killing Fredette, police said.
Named as accomplices were police patrolman Necitas Itchon, Philippine navy seaman Orlando Mystica, Rodante Trinidad and Nicomedes Fabro. The accomplices, who are under police custody, allegedly either supplied or hid the .38-caliber revolver used in the killing. The gun has been recovered, authorities said.
Fredette was walking in Olongapo's entertainment district outside the U.S. Subic Bay Naval base when two men shot and killed him. His slaying was not considered to be politically motivated.
Corpus and Otian were arrested as suspects in a string of robbery cases in Olongapo, 50 miles northwest of Manila, police said.
Two other American servicemen were killed last month outside the U.S. Clark Air Base near Subic.
The 19,000-member communist New People's Army has taken responsibility for the killing of the two Americans.
In all, 10 U.S. nationals have been killed in the Philippines in politically motivated killings over the past three years.
The NPA, which is waging a 21-year rebellion, has vowed to kill more Americans unless the United States dismantles its six facilities in the Philippines. The leases on the facilities expire next year.