Tom Clancy, bestselling author of the Jack Ryan series of novels, which include The Hunt for Red October and Clear and Present Danger, has died. Clancy passed away October 1 in a Baltimore, Maryland hospital at the age of 66. The cause of death was not immediately available, and only reported as a “long illness.”

Clancy’s publisher, Penguin Group, confirmed the author’s passing, with executive David Shanks releasing this statement:

“I’m deeply saddened by Tom’s passing. He was a consummate author, creating the modern-day thriller, and was one of the most visionary storytellers of our time. I will miss him dearly and he will be missed by tens of millions of readers worldwide.”

Clancy became famous with his very first novel, The Hunt for Red October, which was published in 1984 and introduced the world to deeply patriotic CIA analyst Jack Ryan, who would become an iconic character both on the page and on the big screen. Clancy’s books were known for their extremely detailed and technical descriptions of military operations and post-Cold War settings. In 1989, the novel Clear and Present Danger sold 1,625,544 hardcover copies and is the top-selling novel of the entire 1980’s.

Tom Clancy co-founded the video game development company Red Storm Entertainment in 1996, which was later bought by Ubisoft Entertainment. Clancy lent his name to several successful, military operation-themed video game series, including Tom Clancy’s Rainbow SixSplinter Cell and Ghost Recon. He was also a part owner of the Baltimore Orioles.

Thomas Leo “Tom” Clancy, Jr. was born in Baltimore on April 12, 1947. Clancy attended Catholic college prep school Loyola Blakefield, graduating in 1965 before attending Loyola College in Baltimore. He married his wife Wanda in 1969, and the two separated in 1995 before a divorce was finalized in 1999. Before becoming an author, Clancy worked as an insurance salesman and helped run an insurance company.

Clancy’s legacy will forever be tied to his Jack Ryan novels, which were adapted into successful films with first Alec Baldwin in the role (in The Hunt for Red October), before Harrison Ford took over, portraying Ryan in blockbusters Patriot Games (the novel is technically a prequel to Red October) and Clear and Present Danger. Ben Affleck was cast as a younger Ryan in The Sum of All Fears, which was presented as a reboot to the film series but never caught on. Paramount is trying the tactic again, with Star Trek Into Darkness star Chris Pine taking the role in the upcoming Jack Ryan, directed by Kenneth Branagh. Some of his video game properties – namely Splinter Cell and Ghost Recon – are currently being adapted into feature films, as well.

Clancy published 28 books in his lifetime, including several non-fiction books on the military, and gained a strong and devoted following, notably among the armed forces. He was a lifelong conservative Republican, and not afraid to take controversial views, such as criticizing left-leaning politicians for “gutting” the CIA and thus being partially responsible for the terrorist attacks on 9/11.

Harrison Ford as Jack Ryan in ‘Clear and Present Danger’

Still, his loyal following among the military gave him amazing access to research and sources within the defense community, and, in turn, he was ever-loyal to them, telling CNN in 2003:

“I’ll never decide for commercial reasons to put something in that endangers our national security. You just can’t do that. There was one thing, I discussed with a friend of mine in the Royal Navy. I told him a story I knew, and he said, ‘Well, Tom, you may never repeat that, as long as you live.’ And I haven’t.”

Clancy’s was a distinct literary voice, and while the term “techno-thriller” was practically invented for his books, he rejected that label, saying first and foremost: “I write novels.”

Screen Rant would like to express our deepest condolences to Tom Clancy’s family and friends. He is survived by four children from his first marriage as well as his wife Alexandra Marie Llewellyn, whom he married in 1999.

R.I.P. Tom Clancy: April 12th, 1947  – October 1, 2013.