I will be in this area in August, doing some of my own UFO research on and near Campobello Island (located almost directly west from this event).
The whole area up there has some UFO history to it. more to come later.

Shag_Harbor_File_RCAC.pdf
SITREP - UNIDENTIFIED FLYING OBJECT
This is a couple of reports and newspaper clippings combined in one document.
Document date: 1967-10-06
Department: CAF Operations
Author: Col. W.W. Turner
Document type: Report
pages: 13
FOIA: SITREP - UNIDENTIFIED FLYING OBJECT - Shag Harbor
Chris Styles Shag Harbour UFO investigator & with Don Ledger author of Dark Object: The Shag Harbour Incident reveals some new info on the case
link
Part One:
Shag Harbour has a paper trail a mile wide, from various government and military agencies, as well as film of the actual retrieval operation which was shown right across the country on the CBC (Canadian Broadcasting Corporation) evening news. After the event, and after the government's claims that nothing of any import occurred, it faded away completely. Faded, only to be resuscitated 26 years later by the indefatigable Christopher Styles, a researcher from Halifax and MUFON's Assistant Director for Nova Scotia. Chris' work on this case is nothing short of phenomenal, and all the more exemplary considering this was his first formal investigation.
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