Los Angeles (AP) — Jon Landau, the Oscar-winning producer who collaborated closely with director James Cameron on two of the “Avatar” films and the “Titanic,” three of the greatest blockbusters ever made, has passed away. He was sixty-three.

On Saturday, Landau’s family made his passing public. The cause of death was not stated.

Because of his collaboration with Cameron, Landau received three Oscar nominations and the best picture award for “Titanic” in 1997. Together, the two have been responsible for some of the biggest box office successes in film history, such as “Avatar” and its follow-up, “Avatar: The Way of Water.”

In a statement, Cameron paid tribute to “my closest collaborator of 31 years, and a dear friend.” Cameron said, “A piece of myself has been torn away.”