A U.S. District Court judge denied a motion on Thursday for Diana Nemes' release, saying there was "substantial" evidence Nemes posed a flight risk.

Radu and Diana Nemes were arrested by the FBI on Tuesday for extradition to Romania, where they face tax evasion charges.

The Nemes' lawyer appeared in district court on Thursday arguing Diana Nemes should be released because she is approximately five months pregnant, which she argued constitutes a "special circumstance" allowing for release on bail. Nemes also has two young children she needs to care for, the lawyer said.

She argued her client was not a flight risk and that the evidence against her client was weak.

Judge Karen Strombom said there is no presumption of release in extradition cases, unless the person being extradited can show to the court that they are not a flight risk, not a danger to the community, and had other special circumstances.

Strombom said the only possible special circumstance raised was the need for Nemes' two sons to be cared for, but it didn't constitute a legal special circumstance, she said. The children are being cared for by the state, she said.

Strombom set an extradition hearing for 1:30 p.m. May 22.