Craig, Alaska.
The Coulthurst family of 4 plus 4 deckhands were shot and killed on the night of Sept 6 1982 aboard the fishing boat ‘Investor’ (owned by the Coulthursts). Apparently the killer tried to scuttle the vessel about a mile from the docks near a tiny island off the coast, but when this failed he spent the next morning moving to and from the Investor via a small motorboat (according to witnesses). This culminated in the boat being discovered ablaze later that morning, and luckily the emergency services managed to get the boat back to shore before it sank, thus preserving some of the evidence that pointed to murder.
A local deckhand was originally convicted but the ruling was later overturned and police are not looking for anyone else… which I never know means either ‘it’s him but we have no evidence that would hold up in court’ or ‘we have no other suspects and are giving up’.
Some good info in this People article last year:
https://people.com/crime/people-explains-investor-fishing-boat-murders-alaska/