Three adults and two juveniles have been found dead in two Minnesota homes in what police believe is a quadruple murder-suicide.

According to a news release from the Duluth Police Department, officers arrived at a home in the 6000 block of Tacony Street in Duluth around 2 p.m. Thursday, Nov. 7, after one of the resident’s co-workers reported that he had failed to show up at service. Erin Abramson, 47, and her son Jacob Nephew, 15, were found dead inside from gunshot wounds, police said.

Authorities quickly identified Anthony Nephew, 46, Abramson’s ex and Jacob’s father, as a suspect and set up surveillance at his home in the 4400 block of West 6th Street, about a mile away from the original crime scene.

Duluth Police Chief Mike Ceynowa said at a press conference on Friday, November 8 that police used a drone to enter the home, where they found the bodies of Anthony’s ex-wife, Kathryn Nephew, 45, and his son, Oliver Nephew, 7. They also died of gunshot wounds, police said.

Anthony was also found dead in the second home “of what appears to be a self-inflicted gunshot wound,” according to police.

Authorities have not yet confirmed a motive for the shootings.

Ceynowa explained that Anthony had a history of mental health issues and that police had been called to the West 6th Street home several times in the past. He also added that investigators are still in the process of using cellphone data to determine when the shootings occurred.

“Our thoughts and prayers go out to the family, friends and loved ones of the four victims of this tragic incident,” the chief said. “We also want to extend our condolences to both the Duluth and Superior communities as this is a senseless and tragic event.”

Police said there is no threat to the public and the investigation is ongoing.

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Minnesota Public Radio reported that Duluth Public Schools — where Oliver was a first-grader — sent a message to parents about the incident and is offering crisis resources to students.

“This is not something that happens often in our community,” Duluth Mayor Roger Reinert told Minnesota Public Radio. “It’s been a few years since we’ve seen something like this, and we’re going to grieve, but we’re also going to make sure we support those families and support our public safety team.”

If you are experiencing domestic violence, call the National Domestic Violence Hotline at 1-800-799-7233 or go to thehotline.org. All calls are free and confidential. The hotline is available 24/7 in over 170 languages.