This is reported by The Mirror.
Also, the cause of the death of the writer was confirmed by the agent Alice Martel in the commentary Entertainment Weekly.
The most famous books by Jack Ketcham are "The Girl Next Door", "The Box", "The Peaceful Kingdom" and "The Closing Time".
By the way, his novel "The Girl Next Door" is the most famous and is based on the real story of the brutal murder of 16-year-old girl Sylvia Likens in 1965. In 2007 the book was filmed.
As reported earlier in "URA-Inform", at the 93rd year of his life died composer, People's Artist of the RSFSR, laureate of the State Prize of the USSR Vladimir Shainsky.