The trio, believed to be a young boy, a middle-aged man and a woman in her early 20s, were found dead in a home at Biddeston, about 25km west of Toowoomba, just before 7pm.

Queensland police said they are not searching for an offender.

"Initial investigations suggest there is no further threat to public safety," they said in a statement.

Homicide investigators have spent the night at the property combing the scene for clues.

A crime scene remains in place.

The Toowoomba Chronicle reports the trio were related.

They are believed to be a father, daughter and a young boy.

Detective Inspector Dave Isherwood told the Chronicle that a friend discovered the bodies after being unable to contact the man or his daughter.

Ages are yet to be disclosed with all next-of-kin still to be notified.

He said police who attended the scene were left shaken by it.

"We don't know whether there is another person involved although early indications would say that is unlikely," he said,

"We believe one of the deceased may be a child.

"It's tragic when a child is involved in any of these types of instances.

"It's tragic when anyone is placed in a situation like this."

He said the causes of death were still to be officially determined.

"We'll continue to make our investigations to determine the real cause of death.

"We believe the victims may have known the assailant and we don't think that anyone is a danger to the community at this time."

Biddeston, a small farming community, has a population of just more than 300.

A Biddeston business told the Chronicle the owner of the home was a "friendly man who helped out in the community".

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