Marcus Sedgwick, whose books for children and young adults drew critical praise and a devoted following, died at 54, the Guardian reports.

Sedgwick, a native of England, worked in bookselling and publishing before making his literary debut in 2000 with the children’s novel Floodland. He followed that up the next year with The Dark Horse, which earned him a place on the shortlist for the Carnegie Medal, the prestigious British award for children’s literature.

He would go on to be named a finalist for the Carnegie Medal several times, for books including My Swordhand Is Singing, Revolver, White Crow, and Midwinterblood, which won the American Library Association’s Michael L. Printz Award for books written for teenage readers.

In a 2014 interview with BookPage, Sedgwick said he appreciated the “freedom” that writing for young readers afforded him.

“In many ways younger readers are more open minded than older ones,” he said. “More open to strange and wonderful ideas. If you’re writing books and want to push boundaries a little bit, then that's a very good thing.”

Sedgwick was remembered by his admirers on social media. On Twitter, author David Almond wrote, “I’m so sad to hear of the death of Marcus Sedgwick. A gentle and helpful friend and a fearless writer.”

And writer Sally Nicholls tweeted, “The death of Marcus Sedgwick is a great loss to children’s fiction and YA. He was an innovative and unusual storyteller, who always treated his audience with huge respect.”

Michael Schaub, a journalist and regular contributor to NPR, lives near Austin, Texas.