Police are keeping an open mind on the events leading to the grisly discovery of a woman's dismembered body in her own refrigerator and the death of her son, found shot in the head at their home in Bangkok.

Police said on Tuesday people should not jump to hasty conclusions about the case, and instead await the outcome of the investigation. 

For now, investigators were waiting for the autopsy results, which were due within 30 days.

The discovery by a neighbour of the dismembered body of 42-year-old Yuree Thaowan in a refrigerator on the first floor of her two-storey townhouse in Bang Khunthian district, Bangkok, on Monday sent shockwaves through the local community.

Police called to the townhouse also found her son, Sira Somdej, 20, on the floor with a gunshot wound to the head. He was still alive and a handgun was found next to his body. 

Sira, a second-year computer engineering student at Rajamangala University of Technology Krungthep, was later pronounced dead at Nakhon Thon Hospital.

Footage from local surveillance cameras, mobile phone records and other details were still being examined. 

The two neighbours were friends of the dead woman and would be questioned further.

Media reports mentioned earlier that one of the friends who found the body said she went to the house after trying unsuccessfully to phone Yuree since about 8pm on Sunday. She was greeted by her son, who said his mother was not home, and did not want her to go inside. She insisted and entered the house. After she looked around she noticed the fridge was open, and looked inside.

The woman who reported finding the body, Voranut Wongchai, 35, said she did not know of any reason why the son would have committed the crime.  

When she arrived at her friend’s house, Sira had cried and said he wanted to be alone. If she had not found the dismembered body in the refrigerator, Sira may have fled, Ms Voranut said, speaking after giving her account to police. 

A relative said that Sira had been treated for depression two years ago. He did not know whether Yuree and her son had any problems.

Police said a knife and a hammer were used in the murder, and that at this stage of the investigation, there was only one suspect, Sira.