Five former managers from a major crate and pallet manufacturer that employed illegal immigrants pleaded guilty Tuesday, 10 months after federal agents staged sweeping raids at company sites in 26 states.

James Rice, 37, of Houston, an executive regional general manager of IFCO Systems, pleaded guilty to conspiring to employ illegal workers. Robert Belvin, 43, of Stuart, Fla., a former general manager of the Albany IFCO plant, pleaded guilty to two felony conspiracy charges.

The two executives could face up to two years in prison and a $250,000 fine, Assistant U.S. Attorney Tina Sciocchetti said.

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Netherlands-based IFCO Systems NV describes itself as the leading pallet services company in America. It reported $108 million in profits in 2006 on revenues of $647 million.

In April, more than 1,100 people were arrested on administrative immigration charges at more than 40 IFCO sites. More than half of IFCO Systems' roughly 5,800 employees during 2005 had invalid or mismatched Social Security numbers, the government said at the time.

U.S. Department of Homeland Security officials said the raids were part of a stepped-up effort to target employers of illegal immigrants.

Defense lawyers said they reviewed prosecution material that included taped conversations involving their clients.

"Under the circumstances, we thought the only rational thing to do was to plead guilty," said Belvin's lawyer, Terence Kindlon.

Rice's lawyer declined to comment.

Three local plant officials, Dario Salzano, 36, of Amsterdam, N.Y., Scott Dodge, 44, of Elmira, N.Y., and Michael Ames, 44, of Shrewsbury, Mass., each pleaded guilty Tuesday to one misdemeanor.

They could face up to six months in jail and $3,000 fines for each illegal alien employed, though they likely will get reduced terms because they cooperated, Sciocchetti said.

Charges were pending against two other IFCO managers in Houston and Cincinnati.