File picture: Pixabay

Canberra - Three toddlers, including twin 2-year-olds, are among the five people found dead at the weekend inside a western Australia home, police said Monday.

The girls' mother and the grandmother were also found dead in the house in Bedford, in the north-eastern suburb of Perth, the state capital of Western Australia. 

The ages of the children - the third girl was 3-and-a-half - and their relationship to the two women were confirmed by the Western Australia police on Monday. No other details were given.

Police are questioning a man in his 20s who walked into a police station on Sunday in a remote mining town, about 1 400 kilometres north of Perth, and provided information about the incident. 

"The man currently assisting police remains in custody, no charges have been laid at this time," the police said on Monday.

Local media said the man in custody was known to the victims, but his relationship with them is not clear. It is still unclear how long the bodies had been at the house before they were discovered by police.

"It is a tragic thing when incidents like this occur. It does send a ripple through the community of Western Australia," Assistant Commissioner Metropolitan Region Paul Steel said on Sunday.

The incident could be the third multiple killing in Western Australia this year.

It comes after the murder-suicide of three adults and four children by a grandfather in the rural town of Osmington in May, and the alleged shooting deaths of a mother and two adolescent siblings by a man in Perth's north-east in July.