A 57-year-old woman was decapitated allegedly by her daughter in Sydney. According to local police, the incident took place Saturday following an argument between the two.

In a news release, the New South Wales Police Force said the 25-year-old woman attacked her mother at their home. She allegedly decapitated her mother in front of the victim's 4-year-old grandson.

“While police are trained to respond to all types of situations, there’s no getting away from the fact this was a horrific attack,” Detective Superintendent Brett McFadden told reporters Sunday. "This is up there with one of the most significant, most horrific scenes police have to deal with."

Local media identified the accused as Jessica Camilleri and the victim as Rita Camilleri. Neighbors told News.com.au they rushed to the home after hearing a "violent argument," but discovered the 57-year-old's head lying on the sidewalk. When police arrived at the scene they found Rita's body inside the family home.

A 4-year-old boy who was in the home at the time of the incident sustained a minor head injury and was transported to a children's hospital.

On Sunday, Jessica appeared in court where she said she was "in agony" and that she suffered from several mental health issues.

The incident is currently being investigated by local police. Detectives seized a knife from the house for forensic examination, adding that the suspect allegedly used a “number of knives” to kill her mother and cut off her head.

"The detectives are now working meticulously through the information available to us, but it’s a very difficult and challenging investigation," McFadden said. "It is also in its very early stages and as you’d understand there is still a long way to go in this inquiry."

crime scene tape
This is a representational image showing a crime scene tape in Aberdeen, Maryland, Sept. 20, 2018. Getty Images/Mark Makela