A Prior Lake couple busted twice in Minnesota for an tax-fraud scheme that victimized immigrants was sentenced Thursday in Minneapolis to lengthy federal prison terms.

Mark and Ornella Hammerschmidt made a career out of scamming immigrants on phony tax and legal services. U.S. District Judge David S. Doty sentenced Mark Hammerschmidt to 11¼ years in prison — the minimum for his felony offense — plus three years of supervised release. He also must pay $1.8 million in restitution. Ornella Hammerschmidt got four years in prison — the maximum — plus three years of supervised release. She also must pay $45,365 in restitution.

Six victims attended the sentencing hearing and one of them also sent a letter. Three victims, speaking through translators, testified that they'd been financially cheated, mentally and emotionally damaged, and now face uncertain immigration status and employment opportunities.

"I think this room is [too] small to fit all of us who were victims," said Jose Alonso, who along with his wife, testified against the Hammerschmidts.

Both defendants apologized and asked for leniency, noting their responsibilities as parents. Mark Hammerschmidt, 49, said alcoholism had "clouded his judgment," and he downplayed the accusations that he had managed the fraudulent businesses. Ornella Hammerschmidt, 37, a native of Venezuela, said she plans to rebuild her life.

Assistant U.S. Attorney Michelle Jones then urged Doty to consider the victims and impose a sentence that is "severe enough to protect the public" from Ornella Hammerschmidt.

"These people's trust has been violated, and they have been threatened," Jones said. "The government doesn't believe the hardship on her family outweighs the hardship on these people."

Jones called Mark Hamerschmidt the "boss" of a "fraud engine." He "flouted the law, disregarded court's authority and ignored the injuries they've caused to so many people," she said.

Jones said in a prepared statement after the sentencing that "the Hammerschmidts stole nearly $2 million from the U.S. Treasury and exploited hundreds of vulnerable victims for their own financial gain, causing those victims immeasurable harm."

The Hammerschmidts' criminal history dates back more than a decade.

The couple was most recently arrested in April for preparing taxes at a Pro Tax RX franchise in Bloomington — a violation of the terms of their release while awaiting sentencing. The couple pleaded guilty last November to charges that stemmed from a 2012 investigation of their immigration services and tax preparation business, American Group US Inc., which had operated from offices in Shakopee and Winter Garden, Fla. Ornella misrepresented herself as an immigration lawyer, and the couple filed more than 1,000 fraudulent tax returns.

In 2004, federal investigators flagged the Hammerschmidts' business in Orlando, Fla., where they helped foreigners arrange sham marriages. The Hammerschmidts were sentenced in 2009 to three years probation on charges of conspiracy to obstruct justice, witness tampering and destruction of evidence.

Natalie Daher • 612-673-1775