Updated Tuesday at 9:50 a.m.: California preacher Harold Camping said his prophecy that the world would end was off by five months because Judgment Day actually will come on Oct. 21.

Original post: The 89-year-old evangelical Christian radio host who wrongly predicted that Saturday would be "Judgment Day" for most humans tells the Associated Press that he'll "have more to say tonight" about why the "Rapture" ruptured.

Harold Camping wouldn't reveal what he planned to say during the "Open Forum" broadcast on his Family Radio International. "I will be putting out a message in our broadcast," he said from his home in Alameda, Calif., near Oakland.

Earlier, Camping said he was "mystified" and "a little bewildered" about being dead wrong.

STORY: Apocalypse not now

He claimed that only about 200 million people on Earth would be saved in the "Rapture," which would be followed Oct. 21 by a fireball that would consume the planet and the billions left behind.

Camping, a retired civil engineer, predicted the same thing in 1994. He blamed that clairvoyant bust on a mathematical error.