(CNN) -- The former manager of the largest U.S. kosher meatpacking plant was arrested Thursday on federal conspiracy charges of harboring illegal immigrants and aiding and abetting aggravated identity theft, federal officials said.
Agriprocessors, the nation's largest kosher meatpacking plant, is in Postville, Iowa.
Sholom Rubashkin, 49, a powerful member of the Hasidic Jewish community and former head of the kosher plant Agriprocessors, was taken into custody Thursday morning by U.S. Immigration and Customs Enforcement agents.
"This investigation is not closed and is continuing," said Bob Teig, a spokesman for the U.S. Attorney's Office in Cedar Rapids, Iowa.
Rubashkin was arrested in Postville, Iowa, a town of about 2,400 in the northeast corner of the state that is home to the kosher plant.
He faces three counts: conspiracy to harbor illegal aliens for profit; aiding and abetting document fraud; and aiding and abetting aggravated identity theft.
If convicted, the first two counts carry a maximum sentence of 10 years in prison and fines of up to $250,000. The third count carries a mandatory consecutive sentence of two years, Teig said. See photos around "ground zero" of the nation's immigration debate »
ICE spokesman Tim Counts said he could not comment about specifics. "Things are still unfolding," he said.
Calls to Agriprocessors seeking reaction have not been returned.
Rubashkin made an initial court appearance Thursday afternoon, where he waived his right to a preliminary hearing. He was released on the following conditions: He must wear an ankle bracelet that tracks his movement, limit his travel to northern Iowa, surrender his passport and his wife's passport and provide a $1 million appearance bond with $500,000 to be secured by Wednesday, according to the prosecutor's office.
ICE agents raided the Agriprocessors plant May 12 and arrested more than 300 illegal aliens, most of whom pleaded guilty to identity theft charges in trials that lasted less than two days. Rubashkin was the plant manager at the time of the raid. Read how the Postville raid angered a local priest
"None of the undocumented alien workers were in possession of documents allowing them to work or reside in the United States legally," the affidavit against Rubashkin says. "During the execution of the warrants, agents discovered and seized dozens of fraudulent permanent resident alien cards from offices within the human resources department at Agriprocessors."
Thursday's arrest came a day after a human resources manager pleaded guilty to conspiracy to harbor illegal immigrants and aggravated identity theft charges. Laura Louise Althouse, 38, faces a mandatory sentence of two years in prison and a potential maximum of 12 years in prison, according to the U.S. attorney's office.
"Althouse conspired with others to harbor undocumented aliens at her place of employment in Postville. The information states the harboring offense was committed for the purpose of commercial advantage and private financial gain," the district attorney's office said in a written statement.
Rubashkin and his father, plant owner Abraham Aaron Rubashkin, face other serious allegations from the state of Iowa. The state has filed more than 9,000 misdemeanor charges against the owners and managers at Agriprocessors, accusing them of child labor law violations.
The criminal complaint, filed by the office of Iowa Attorney General Tom Miller, says the violations involved 32 youths under the age of 18, including seven under the age of 16.