Claim: Night of the Grizzlies, written by Jack Olsen and published in 1969, documented the attack of two campers by grizzly bears, who are considered more aggressive compared to black bears.
Evidence: Night of the Grizzlies (1969) is a book by Jack Olsen which details events surrounding the night of August 13, 1967, when two young women were separately attacked and killed in Glacier National Park, Montana, by grizzly bears. June 1, 1969 Grizzlies are considered more aggressive compared to black bears when defending themselves and their offspring.