Leadership Conference on Civil Rights

Among the millions of clips on the video-sharing Web site YouTube are 11 racially offensive Warner Brothers cartoons that have not been shown in an authorized release since 1968.

Some of the cartoons were removed on April 16. A message saying the cartoons were no longer available because of a copyright claim by Warner appeared in their place. By evening the messages disappeared, and some of the cartoons were back. Representatives for YouTube and Warner would not confirm whether the companies had tried to remove the cartoons.