Harold Camping, the California preacher who used his evangelical radio ministry and thousands of billboards to broadcast the end of the world and then gave up public prophecy when his date-specific doomsdays did not come to pass, has died at age 92.

Camping’s most widely spread prediction was that the Rapture would happen on May 21, 2011. His independent Christian media empire spent millions of dollars — some of it from donations made by followers who quit their jobs and sold all their possessions— to spread the word on more than 5,000 billboards and 20 RVs plastered with the Judgment Day message.

When the Judgment Day he foresaw did not materialize, the preacher revised his prophecy, saying he had been off by five months. The preacher, who suffered a stroke three weeks after the May prediction failed, said the light dawned on him that instead of the biblical Rapture in which the faithful would be swept up to the heavens, the date had instead been a “spiritual” Judgment Day, which placed the entire world under Christ’s judgment.

But after the cataclysmic event did not occur in October either, Camping acknowledged his apocalyptic prophecy had been wrong and posted a letter on his ministry’s site telling his followers he had no evidence the world would end anytime soon, and wasn’t interested in considering future dates.

Camping graduated from the University of California, Berkeley in 1942 and started a construction business shortly after the end of World War II, according to his nonprofit’s website.

For decades, Camping and his family attended the Christian Reformed Church, where he served as an elder and Bible teacher, but he left the church in 1988 when he felt it no longer faithfully represented biblical teachings, associates said.

He formed his Family Stations ministry in 1958 and eventually sold his business to become the group’s president and general manager as a full-time volunteer. In 1961, Camping began hosting the Open Forum program, which was broadcast in 30 languages online and on a network of more than 140 domestic and international radio stations owned by Family Stations.

Each weeknight, Camping would transmit his own biblical interpretations in a quivery monotone, clutching a worn Bible as he took listeners’ calls. He first predicted the world would end on Sept. 6, 1994 and when it did not, Camping said it was off because of a mathematical error. Followers later said he was referring to the end of “the church age,” a time when human beings in Christian churches could be saved.

After his billboards warning of pending doom popped up across the country in 2010 and 2011, Christian leaders from across the spectrum widely dismissed his prophecies while atheists and revelers poked fun at his prediction. Some also criticized Camping’s use of millions of dollars in followers’ donations to advertise Judgment Day.

Camping also offered a measured apology, adding that he felt so terrible when his prophecy did not come true that he left home and took refuge in a motel with his wife.

“If people want me to apologize, I can apologize,” he said in response to questions about some listeners’ decision to give away their possessions in anticipation of the Rapture. “I pray all the time for wisdom.”

Camping wrote about 30 books and booklets over the years, many from his modest brick home in Alameda, a leafy Oakland suburb. Family Radio Network said in its statement that he is survived by a wife of 71 years.

“We know that each of us remain in God’s hand, and God is the One who knows our appointed time to leave our earthly body behind,” the statement said.