A world champion shooter allegedly killed his model wife and their child before turning the gun on himself.

Konthorn Suchakum, 39, who was a member of the Thai national shooting team, reportedly suffered from severe stress and heartbreak following the death of his father in September.

Konthorn, his wife Sirirak Manthanajaru, 42, and their nine-year-old daughter Kanyakorn lived in a four-storey building in Bangkok, Thailand and were last seen alive by their housekeeper, Butsabong Meekhunsut, 50, who left the home on October 20 at 11 pm.

When Butsabong returned the next morning, she discovered the family already dead with gunshot wounds to their heads.

Footage shows police investigating the crime scene as an ambulance and forensic officers arrived at the location on October 21.

Officers said that Konthorn competed in the Asian Games, SEA Games, and various ISSF World Cup events. His wife was a model and events presenter. They believe he killed his wife and daughter before shooting himself with the weapons he had stored at home.

Police Colonel Somsit Santatsanachoke, superintendent of Bangkok Noi district station, said: 'We believe that Konthorn was easily angered and may have been under stress before the incident, causing him to go on a rampage and shoot his daughter and wife before taking his own life.

'We are investigating his family members and close associates to determine the motive behind this incident.'

Authorities examined the building, which served as the family's home, with signage bearing the name of Konthorn's father, retired Police Colonel Udomsak Suchakum.

They found the lifeless daughter lying face up in a pool of blood with a gunshot wound to her cheek on the third floor. She was wearing a long-sleeve pajama top and pants with a cartoon print.

The wife was found hugging her daughter's leg while wearing a floral print shirt and blue pants. She was reportedly shot once in the back of the neck, with the bullet exiting through the front, and twice more in the chest.

Konthorn, who specialized in trap shooting and shotgun, was found lying on top of his wife's leg with a gunshot wound to his head and a 9mm pistol nearby. He was wearing a black short-sleeve shirt and grey shorts.

The housekeeper, who first found the bodies, told police: 'I work at the house but do not live there. Konthorn was stressed and had not slept for several days after his father died on September 26. I did not notice anything strange when I left the home.'

Police also interviewed neighbours who said Konthorn liked to handle guns and frequently had disputes with others in the area.

However, his father, a retired police colonel, would always mediate and resolve the issues.

One neighbour said: 'We always forgave him and did not hold a grudge out of respect for his father, but after his death, we were too afraid to intervene with Konthorn to avoid conflict.'

A day before the killings, authorities said Konthorn filed a missing firearms report at Bangkok Noi Police Station, claiming he had lost three guns.

Authorities said they are still investigating the deaths.

The superintendent added: 'We have assigned a rescue team to transport the three bodies to Siriraj Hospital for autopsy before allowing their relatives to retrieve them for the funeral.'