The Rockport man accused of killing four people, including his mother and grandparents, in Massachusetts last fall has been indicted on four counts of first-degree murder.

Orion Krause, 22, will be arraigned on those charges in Middlesex Superior Court in Woburn Massachusetts, according to his attorney, Edward Wayland. Arraignment is set for 9 a.m. April 11, according to the Middlesex district attorney’s office.

Krause was deemed mentally fit to stand trial in October. The indictments against Krause were handed down by a Middlesex County grand jury on March 29.

Krause is accused of killing his mother, Elizabeth “Buffy” Krause, 60; her parents Elizabeth “Esu” Lackey, 85, and Frank Danby “Dan” Lackey III, 89; and their home health aide, Bertha Mae Parker, 68.

[Unsealed police reports in quadruple slaying case offer grisly details]

Krause has been in custody since he was arrested for the Sept. 8 killings. He is being held at Bridgewater State Hospital, according to Wayland.

Krause allegedly admitted to investigators that he committed the killings with a baseball bat at his grandparents’ home in Groton, Massachusetts, according to police reports from the Sept. 8 incident.

Police found the bodies of Krause’s mother and grandparents sitting in chairs in the kitchen. Parker’s body was found in a flower bed, according to the report.

Krause allegedly told investigators that he “freed them.”

[Former babysitter of Mainer accused of killing 4 recalls ‘Little Orion’]

One investigator wrote in the report that when asked where the deaths happened, Krause allegedly pointed to the woods. Investigators found a wooden baseball bat with what appeared to be blood on it under a tree in the backyard.

On the night of the killings, Krause allegedly called a former college professor and said, “I think I have to kill my mom.”

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