MINNEAPOLIS (WCCO/AP) — Two men convicted for fraud have escaped from a low-security federal prison camp near Duluth, Minn., according to authorities.

According to a source from the U.S. Marshal Service, prison officials were doing a prison count on Saturday night when they realized 64-year-old Michael Krzyzaniak and 67-year-old Gerald Greenfield were missing.

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The prison holds prisoners “on the honor system,” instead of having locked cells.

The men were discovered missing from the camp during the 10 p.m. head count Saturday, prison spokesman David Baker said. The camp is on the former Duluth Air Force Base.

“We are a minimum-level facility, so to the best our knowledge they walked away,” Baker told The Associated Press. “There’s not a secure perimeter there. They’re nonviolent offenders.”

Although neither man is considered dangerous, Baker said anyone who sees them should call 911.

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Greenfield was scheduled to be released in November 2015. Krzyzaniak’s sentence runs until April 2022.

Krzyzaniak is serving a 12-year sentence for bilking investors out of nearly $26 million.

Greenfield is serving a four-year sentence for conspiracy to commit money laundering in a $2.5 million mortgage fraud scheme.

Anyone with information about their whereabouts is asked to call 911.

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