The couple’s 29-year-old son and a 35-year-old man, who is believed to be his friend, were jointly charged with two counts of murder on Sunday, a police spokeswoman told AFP.
The men appeared at a magistrates’ court on Monday but no plea was recorded, according to public broadcaster RTHK. They will remain in custody until the next court appearance on May 13, the broadcaster added.
Local TV showed one of the suspects being brought to court with his face covered by a black hood.
“The investigation continues on the motive of the case,” the spokeswoman said, adding that police were still looking for missing parts of their bodies.
The couple’s severed heads were reportedly found by police in a refrigerator at a bloodstained apartment on the outskirts of the southern Chinese city on Friday. Parts of their arms and legs were found elsewhere in the flat.
Police divers failed to recover any parts after a search at sea near the apartment over the weekend.
Post-mortem examinations will also be carried out on the 64-year-old man and his wife, aged 63.
The couple were reported missing by their eldest son on March 9.
The suspect, their younger son, told police that his parents were travelling to mainland China but police became suspicious after they failed to find records of the couple leaving the city, the South China Morning Post said.
Police detained the duo on Friday and the arrests led police to the building where the victims’ heads were found, along with saws, knives, a chopping board, plastic boxes and bags containing other body parts, the Post said.
Murder is punishable with life imprisonment in Hong Kong.