ROCKPORT — A Rockport man pleaded guilty Sept. 1 to the murders of his mother, his grandparents and their caretaker in Massachusetts four years ago.

Orion Krause, 26, of Rockport, pleaded guilty in Lowell Superior Court to four charges of second-degree murder in connection with the slaying of his mother, Elizabeth Lackey Krause, 60; grandparents Frank Darby Lackey III, 89, and Elizabeth Lackey, 85; and their home healthcare worker, Bertha Mae Parker, 68, in Groton, Mass., according to a news release posted on the website of Middlesex County District Attorney’s Office.

Judge Kenneth W. Salinger sentenced Krause to life in prison, with parole eligibility at 25 years.

“The resolution of this case today, in no way, can erase the incalculable loss felt by the family and friends of these victims,” Middlesex District Attorney Marian Ryan stated in the news release. “Following the 2017 murder, the entire Groton community mourned the loss of Elizabeth and Frank Lackey, Elizabeth Krause and Bertha Mae Parker. We continue to have them in our thoughts today as this case comes to a close.”

Krause’s attorney, Edward Wayland said Krause spoke during the Sept. 1 hearing.

“I could not quote him, but he responded briefly and with emotion to the victim impact statements. Particularly the one given by the daughter of Bertha Parker,” Wayland said.

The case was scheduled to go to trial starting Sept. 7.

The defense entered in March 2019 a not-guilty plea for Krause based on lack of criminal responsibility due to mental disease or defect. The state conducted a forensic evaluation of Krause. While the results of that forensic report were not released, if the prosecution agreed he was not criminally responsible, a trial would not have been scheduled.

Krause was indicted in March 2018 by a Middlesex County grand jury on four counts of first-degree murder. First-degree murder carries a mandatory sentence of life in prison.

Documents filed in court after his arrest detailed that his mother called police from her home in Rockport the night before the murders, concerned about whether he might harm himself.

She later told the dispatcher her son was a “very mild soul,” and that there were no drugs involved.

About 20 hours later, police were called to the Lackeys’ home in Groton and found the bodies of the four victims.

An hour before their bodies were found, a professor with whom Orion Krause studied at Oberlin Conservatory in Oberlin, Ohio, phoned Rockport police to tell them that Krause called to say he planned to kill his mother.

Oberlin College Prof. Jamey Haddad reported that Krause stated he “done something bad,” and stole some money and his mother’s car. Krause stated to Haddad twice during the conversation, “I think I have to kill my mom.” The professor’s wife called police in Maine after trying to reach Orion Krause’s mother.

Police said Orion Krause called his mother, and said he was in Boston and needed a ride home. Police have not said what happened to the car he was driving.

When his mother picked him up, she took him to her parents’ home in Groton, located about 40 miles northwest of Boston.

Orion Krause stopped, naked, covered in mud, with some blood on him, at a home in his grandparents’ neighborhood to tell the residents he killed four people.

Krause repeated his statement to police that he killed four people and identified who they were to police, according to the police report.

Orion Krause also told a nurse during a medical evaluation after his arrest that he used heroin, according to the police reports.

Krause was a 2013 graduate of Camden Hills Regional High School in Rockport and graduated in May 2017 from Oberlin, where he studied music.

Friends said Krause was a kind, musically gifted person.

Rockport police had one contact with Krause about a year before the killings, but the details of that matter have not been released. Rockport/Camden Police Chief Randy Gagne said at the time it was not a criminal matter.