Fox News commentator John Gibson apologized on his TV show, The Big Story, Thursday for remarks he made on his radio talk show the previous day about the death of Heath Ledger. During the show, he had mocked the late actor as a "weirdo" with a "serious drug problem" and laughed that he may have killed himself in reaction to the plunge in the stock market. He then played a clip from Brokeback Mountain -- a movie that Gibson had once described as a "gay agenda movie" -- in which Ledger utters the famous line "I wish I knew how to quit you." Well, Gibson mocked, "he found out how to quit you." He then played another clip in which Ledger remarked, "We're dead," then repeated the line himself laughing. On Thursday's telecast, Gibson said, "To anyone offended by my comments, I'm sorry. But I'm also sorry Heath Ledger is no longer alive and with us." The gay-rights group GLAAD said it planned to send a petition to Fox News asking why it continues to provide a platform for Gibson's "cruel and tasteless comments."