A Brother's birthday present.

BOSTON, Massachusetts: A man on a rampage fatally stabbed his 17-year-old sister, decapitated his five-year-old sister in front of a police officer and then headed toward his nine-year-old sister with a knife in his hand before officers shot him amid what the local police chief described as "a killing field".

There was no clear motive for the savagery that occurred on Sunday (AEDT) in Milton, a wealthy Boston suburb. But there was no doubting the carnage committed by Kerby Revelus, 23, against his three sisters in the home they shared with their parents and grandmother.

Bianca was killed as a cake for her fifth birthday sat on the kitchen table. Sarafina, 9, dialled the emergency unit and then saw police shoot her brother as her elder sister, Samantha, lay dead on the floor.

Sarafina was hospitalised at the Boston Medical Centre with defensive wounds to her hands and stab wounds in her abdomen and one of her legs.

"In policing, we see raw human emotion every day, but to think a human being could afflict such an atrocious, violent act on his own family is unbelievable," Milton police chief Richard Wells said.

"When I walked up to the first officer on the scene, I could see the whole story right in his face. It just told me this was something very bad."

Kerby Revelus had recently served time in jail on a gun charge. Police had been called to the same house in 2004 after a domestic violence report of Revelus allegedly punching one of the women living in the home.

The attack came about 24hours after Revelus had been in a fist-fight with a man living next door, Mr Wells said.

Investigators believe Revelus targeted Samantha, a student at Milton High School, and fatally stabbed her with a knife while their grandmother was doing the laundry in the house's basement.

Sarafina, a student at the Tucker Elementary School, called the police emergency dispatcher just before 5pm local time. An officer on patrol in the neighbourhood arrived within a minute, Mr Wells said, and could hear an altercation inside as he reached the second floor.

Revelus was in the act of decapitating Bianca as the officer entered the room. "The officer actually walked into a killing field. He walked into such carnage, as far as the atrocity of it, I've never seen it," Mr Wells said.

Within moments, four back-up officers were inside and two of them shot Revelus as he tried to get to Sarafina. Revelus fell dead, still clutching the knife.

The house Where it happened.


The Birthday Girl

The oldest sister who was killed, and the younger who actually survived.

And the lovely parents who decided to bury the sisters with their loving brother.