Human error is to blame for an offensive link at Wal-Mart’s Web site that recommended a film about Martin Luther King Jr. to potential buyers of a “Planet of the Apes” DVD, the retail company said Friday.

The mistake resulted from a well-intentioned effort to promote a DVD about the black leader, said Carter Cast, president of walmart.com, the online shopping arm of Wal-Mart Stores Inc.

A business manager had grouped “Martin Luther King: I Have a Dream” with three other black-themed movies and assigned the package an overly broad category of DVD boxed sets, Cast said.

Wal-Mart removed the feature from its Web site Thursday after learning of the juxtaposition from reporters. Wal-Mart apologized and shut down indefinitely its entire online system for referring shoppers to other movies.