LOS ANGELES (Reuters) - Casino owner Steve Wynn was awarded $20 million in punitive damages on Tuesday in his defamation suit against "Girls Gone Wild" creator Joe Francis, adding to $20 million he won in compensatory damages a day earlier.

The 70-year-old Las Vegas mogul had accused Francis, 39, of slander for claiming that Wynn wanted him killed and buried in the desert over a gambling debt. A Los Angeles County Superior Court jury deliberated just four hours before returning its verdict in the second phase of the trial.

Wynn won a $7.5 million judgment against Francis earlier this year in a separate defamation case.

(Reporting by Steve Gorman; Editing by Cynthia Johnston)