GROTON (CBS) — Four people are confirmed dead in a reported quadruple homicide in Groton.

Three adult women and one adult man were found.

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An ambulance leaves a Groton home where four people were killed. (WBZ-TV)

The Massachusetts State Police say the incident took place on Common Street in that Middlesex County town.

District Attorney Marian Ryan addresses a quadruple homicide in Groton. (WBZ-TV)

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Middlesex District Attorney Marian Ryan reports that a weapon has been recovered but would not give any details about the suspected weapon.

Groton Police Chief Donald Palma says he believes some of the people knew each other and that the incident is not random.

Middlesex District Attorney Marian Ryan And Groton Police Chief Donald Palma News Conference

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Middlesex District Attorney Marian Ryan and Groton Police Chief Donald Palma say they are officially opening a homicide investigation.