Police responded to a call reporting a stabbing call at around 12:30 PM at 26 Taft Street in Dorchester.
Upon arriving, police found one woman who was pronounced dead on the scene. A second woman was rushed to a hospital and later pronounced dead as well.
There were children also at the home at the time, and they were taken to a hospital as well.
A dog was injured, but was being cared for by the MSPCA, police said.
One man is in police custody.
Police were still investigating and hadn't yet released the reason for the stabbing on Sunday afternoon.
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