A woman accused of killing three of her children with the help of her 16-year-old son has admitted to committing the crime, according to Los Angeles police investigators.

The 38-year-old woman called Angela Dawn Flores and the teenage boy were arrested on Sunday morning from their house in San Fernando Valley . The police had received a call from the family's neighbours stating that they could hear screams from a house.

The police rushed to the crime scene and found bodies of three children, including a 12-year-old girl and twin boys, who were eight. The paramedics said it appeared that they had been dead for several hours.

The mother was immediately detained for questioning and was taken to a hospital for a mental evaluation. She has been booked on suspicion of three counts of murder with her bail set at $6 million.

The oldest sibling was also arrested in connection with the incident. He is being held without bail at Sylmar Juvenile Hall.

The cause of the deaths and the identities of the victims have not been revealed by the authorities yet. Flores is the mother of seven children. Her three other children live out of state with their father.

The family had moved to the neighbourhood just three months prior to the brutal incident. Prisila Canales, a neighbour of Flores, told The Los Angeles Times: "I heard someone screaming, 'My family is abusing me,' and all kinds of nonsense. I couldn't make out what it was."

Another neighbour, Blanca Hernandez, said that the woman sat on the porch of her house for several hours on Saturday, shouting and acting erratically. The family often had arguments that could be heard by neighbours, according to a report in CBS News.

Police Line
Crime scene police line | Representational Image Photo: GETTY IMAGES / SCOTT OLSON