Hollywood director Ron Howard has led tributes to Oscar-winning Titanic composer James Horner, who has died at the age of 61.
According to reports, Horner was killed when his two-seater single-engine plane crashed in southern California.
Howard wrote on Twitter: " Brilliant Composer James Horner, friend & collaborator on 7 movies has tragically died in a plane crash. My heart aches for his loved ones."
The Hollywood Reporter said Horner's personal assistant, Sylvia Patrycja, confirmed the news on her Facebook page.
She wrote: "A great tragedy has struck my family today, and I will not be around for a while. I would like some privacy and time to heal. We have lost an amazing person with a huge heart, and unbelievable talent. He died doing what he loved. Thank you for all your support and love and see you down the road. Love Sylvia."
A Ventura County fire spokesman confirmed that a plane registered to Horner had crashed, that the pilot had died and no-one else was on board.
A lawyer for Horner, Jay Cooper, said the aircraft was one of many owned by the composer. He added that no-one had heard from Horner since the crash.
Mr Cooper said: "It was his plane and, if he wasn't in it, he would've called."
Stars across the globe have been remembering Horner, who had 10 Academy Award nominations, including two wins for Titanic.
Horner also famously worked on Braveheart, and actor Russell Crowe paid tribute to him, writing: "My sincere condolences to the family, loved ones and friends of James Horner. #abeautifulmind".
Horner's representative has been contacted for comment, but has not yet responded.
American composer Steve Jablonsky, best known for his music in the Transformers movie series, tweeted: " James Horner, thank you for inspiring a young me to pursue a career in film music. Thank you for your music. Rest in peace."
The Amazing Spider-Man director Marc Webb also paid tribute to Horner, writing on Twitter: "Last time I spoke to JH he was scoring for a kid at AFI. 2 Oscars and he agreed to score a student film! What generosity. #RIPJamesHorner."
The agency in Los Angeles who represents Horner has said they are still awaiting confirmation that he was the pilot.
In an official statement, the Gorfaine/Schwartz Agency added: " We are shocked and deeply saddened to learn that his single-engine aircraft was involved in a fatal crash yesterday morning in northern Ventura County.
"Our thoughts and prayers remain with James' family at this difficult time.
"We can offer no further comment for the time being, except to ask that the family's privacy be respected in the days ahead."