Tributes have been pouring in for Casey Kasem, who died on Sunday after a long illness.

Ryan Seacrest, who took over as American Top 40 host when Casey stepped down in 2004, said in a statement, "It’s a sad day for the broadcasting community and for radio listeners around the world. When I was a kid, I would listen to Casey Kasem’s AT40 show every weekend, and dream about someday becoming a radio DJ. So when decades later I took over his AT40 countdown show, it was a surreal moment. Casey had a distinctive friendly on-air voice, and he was just as affable and nice if you had the privilege to be in his company. He’ll be greatly missed by all of us."

Carson Daly tweeted: "Long before MTV and the Internet #CaseyKasem made sure you were hearing the best music out there. Peace be to his family and RIP. #Respect"

Nikki Sixx -- who had co-hosted his radio show Sixx Sense With Nikki Sixx with Casey's daughter -- tweeted: "RIP Casey Kasem who inspired all of us in radio & turned millions of people onto music. Sending love to @KerriKasem, family and friends."

Al Roker tweeted: "Casey Kasem didn't deserve the public indignity by his family in his final days. He left us on Sunday: AT40 day."

Scott Baio tweeted: "RIP Casey Kasem. This last long distance dedication is for you. Prayers to his loved ones."

Dave Coulier tweeted: "RIP Casey Kasem. I was lucky enough to work with him on Scooby Doo. A very talented man who'll be missed by so many."

Bryan Adams tweeted: "RIP DJ Casey Kasem. One of the greats of American radio."

Marie Osmond tweeted: "We've lost a music industry icon. Changd the industry w/AT40 Cntdwn. RIP Casey Kasem."

Nancy Sinatra tweeted: "Casey Kasem, one of the most decent men I ever knew...'keep reaching for the stars...' look for The Light, godspeed."