The Boston Herald is reporting that call logs show an officer was dispatched to a Lynnfield, Massachusetts, house that ended with one man dead.
Police were dispatched to the gated mansion for a property check, just after 9 p.m. last Saturday.
The call was cleared about nine minutes later, but some six hours later, Keivan Heath was shot and killed at that home.
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He was one of dozens of guests at the home.
Two off-duty Boston police officers were also at the party and are cooperating with the investigation.
No arrests have been made.