Ken Spears, the co-creator of the cartoon series Scooby-Doo, has died at the age of 82.
Spears, who created the animated characters alongside his creative partner Joe Ruby, died of complications from Lewy body dementia.
Their original show, Scooby Doo, Where Are You!, only ran for two series from 1969-1970, but established a template that spawned 50 years of stories.
Spears' death comes three months after that of his co-creator, Ruby.
His son Kevin confirmed to The Hollywood Reporter that Spears died in Los Angeles on Friday.
Warner Bros president Sam Register said in a statement: "Warner Bros Animation is saddened to learn of the passing of Ken Spears and we send our warmest thoughts to his loved ones.
"He was a true innovator in the industry whose gifts of humour and storytelling continue to delight audiences.
"You cannot find a screen in the world that has not played a version of Scooby-Doo. We continue to be inspired by his work at Warner Bros. Animation and are honoured to carry on the legacy of his beloved characters."
Sam Register, president of Warner Bros. Animation and Cartoon Network Studios, honors #ScoobyDoo co-creator Ken Spears: "He was a true innovator in the industry whose gifts of humor and storytelling continue to delight audiences" https://t.co/OIwI8woYvW— Variety (@Variety) November 10, 2020
Ken Spears was born in Los Angeles on 12 March 1938, and met Ruby when both were sound editors and staff writers at animation studio Hanna Barbera.
While there, the pair created Scooby-Doo, Where Are You!, which debuted on CBS in September 1969.
It followed the adventures of a cowardly but good-natured Great Dane, Scooby, who travelled the US solving spooky mysteries with a group of plucky teenagers - Daphne, Fred, Velma and his slacker sidekick, Shaggy.
Spears and Ruby wrote and story-edited all but four of the first 25 episodes.
The pair went on to create characters including Dynomutt, Dog Wonder and Jabberjaw and were asked to supervise the Saturday morning cartoon line-up at CBS, and later did the same job at ABC.
In 1977, ABC set up Ruby-Spears Productions, which went on to spawn series such as Mister T and Alvin and the Chipmunks.
After Spears' death was announced, the official Scooby Doo Instagram account paid tribute, with an image of the Scooby Doo gang captioned: "Ken Spears 1938-2020."
"Ken will forever be remembered for his wit, his story-telling, his loyalty to family, and his strong work ethic," Kevin Spears said in a statement to Variety.
"Ken has not only made a lasting impression on his family, but he has touched the lives of many as co-creator of Scooby-Doo. Ken has been a role model for us throughout his life and he will continue to live on in our hearts."