Best-selling author and gay activist E. Lynn Harris died Thursday night at the age of 54. The cause of death has not yet been officially determined, but Essence reports the author recently suffered a â€œserious health setbackâ€ duringÂ a book tour for his novel Basketball Jones.

E. Lynn Harris was widely known for his literary novels featuring closeted and openly gay men struggling for acceptance and success in the face of societal prejudice. At his death, Harris had published more than 2 million copies of his works. Harris rose from humble beginnings selling his first novel, Invisible Life, out of the back of his car and at local beauty salons. The book was later picked up and published nationally by Anchor books.

Some of Harrisâ€™ other novels included If This World Were Mine, Any Way the Wind Blows and A Love of My Own. Harris won numerous awards for his books, including the James Baldwin Award for Literary Excellence. In all, Harris published 11 novels throughout his literary career. Harris also recently taught as a visiting professor at the University of Arkansas.

Harris reportedly became ill while on tour in support of his most recent novel Basketball Jones. Publicist Laura Gilmore stated that Harris died after being â€œstrickenâ€ at the Peninsula Hotel in Beverly Hills, according to WSBTV.com. The Los Angeles coronerâ€™s office reports that a man matching Harrisâ€™ name and date of birth died Thursday night at Cedars-Sinai Medical Center.

In a press statement, Doubleday Executive Director of Publicity Alison Rich said that the company â€“ which published Harrisâ€™ novels â€“ is â€œdeeply shocked and saddened to learn of [his] death at too young an age. His pioneering novels and powerful memoir about the black gay experience touched and inspired millions of livesâ€¦ Lynn was a warm and generous person, beloved by friends, fans and booksellers alike, and we mourn his passing.â€

R.I.P.