Maine Multiple Murderer Dies in Massachusetts Prison at 36

A Maine man who killed his parents and their 2 friends before a shooting spree on I-295 has died in prison.

Maine Man Who Killed His Parents and 2 Others in Bowdoin Dies in Prison

Joseph Eaton was 34 years old when he fatally shot his parents, Cynthia and David Eaton, and their friends, Robert and Patricia Eger. He had been released from prison just days before the fatal shootings, which took place at the Eger's home.

Cynthia and David were in Maine to pick their son up upon his release from prison.

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After the killings, Joseph Eaton went to Yarmouth, where he opened fire on vehicles traveling on I-295.

One northbound vehicle was struck by gunfire, as were three southbound vehicles. Three people were taken to the hospital with gunshot wounds.

A Maine Man Who Killed 4 People Died in a Massachusetts Prison

Eaton never gave any explanation for the killings, but pleaded guilty in a plea deal. He said he opened fire on the interstate because he thought the other vehicles were with the police.

Joseph Eaton was sentenced to life in prison, which he was serving in Massachusetts.

Death of a Maine Multiple Murderer in Massachusetts Prison is Under Investigation

Julia Keane of the Worcester, Massachusetts District Attorney's Office confirmed that 36-year-old Joseph Eaton died while incarcerated at the Souza-Baranowski Correctional Center in Lawrence, Massachusetts.

The cause and manner of his death are now under investigation by the Massachusetts State Police.

We'll update this story as more details become available.