Two Roman Catholic priests stole millions in offerings and gifts made to their parish over several years, authorities said Thursday.

Monsignor John Skehan, who was pastor at St. Vincent Ferrer Catholic Church for four decades, was arrested Wednesday night on charges that he stole $8.6 million from the church, using the money to buy property and other assets, investigators said.

The 79-year-old priest was arrested at Palm Beach International Airport as he returned from Ireland and was being held on $400,000 bond on grand theft charges.

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The Rev. Francis Guinan, who succeeded Skehan three years ago, has disappeared and was being sought, authorities said. He is alleged to have stolen an unspecified amount of money to take gambling trips to Las Vegas and the Bahamas.

"Millions of dollars that should have gone to helping the homeless folks or the school itself" didn't, said Amos Rojas Jr., a special agent with the Florida Department of Law Enforcement.

An anonymous tip in June 2005 led police and the church to launch the investigation.

An audit of church books detected the theft and the investigation continues to find possible misappropriation, said Preston Mighdoll, assistant state attorney in Palm Beach County.

Investigators say Skehan created several "slush" accounts, and instructed church workers to funneled there to hide it from the Palm Beach Diocese. The thefts began in 2001, police said.

Skehan is charged with grand theft of $100,000 or more between September 2001 and January 2006, while Guinan faces the same charge for activity from September 2003 to April 2005.

Specifics about where most of the $8.6 million went or precisely how it was taken were not included in court records.

Skehan's attorney, Ken Johnson, said he thought the multimillion dollar figure was "over sensationalized."

"My reading of the probable cause affidavit indicates that the amount of money he's actually accused of misappropriating amounts to about $325,000, which is a far cry from $8.6 million," Johnson said.

Bishop Gerald M. Barbarito of the Diocese of Palm Beach said the two priests were placed on administrative leave and will not have permission "to exercise publicly their priestly ministry" until the criminal matter is resolved.

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