ST. CLAIRSVILLE — Mark Thomas, formerly a St. Clairsville attorney and Belmont County commissioner, appeared before a federal judge following his arrest for mail fraud on Tuesday.

Thomas is facing four charges of felony mail fraud stemming from allegations that he abused his status as power of attorney and stole more than $500,000 from an elderly client with dementia.

Thomas, 61, was indicted last week by a federal grand jury. Local law enforcement and FBI agents attempted to serve a warrant at his residence but did not find him there.

On Tuesday morning, though, St. Clairsville police saw his vehicle and executed a traffic stop in the alley behind the St. Clairsville Public Library. He was arrested and transported to the Belmont County Jail on a federal warrant. He was held there without bond until shortly after noon, when federal authorities arrived to transport him to another location.

If convicted of all four mail fraud charges, Thomas could serve 20 years in prison.

Jennifer Thornton, spokeswoman with the U.S. Department of Justice office in Columbus, said Thomas was scheduled for his initial appearance in federal court at 3 p.m. Tuesday.

“The United States is not seeking detention in this case, so Thomas will likely be released on bond conditions,” she wrote in an email. “The next step would be an arraignment.”

According to the clerk’s office at the federal courthouse in Columbus, as of closing time there were no new docket entries as a result of the hearing, but it is expected to be updated today.

Thomas appeared before Magistrate Judge Chelsey Vascura. Chief Judge Algenon Marbley is assigned to Thomas’ case.

According to the indictment, Thomas is accused of defrauding a client from 2012 through August 2019 while serving as her power of attorney. It is alleged that Thomas took the victim’s money without her knowledge or permission to use for his own benefit.

The woman was 85 years old at the time the alleged crimes began. The indictment states that Thomas improperly used the victim’s power of attorney and his status as a lawyer — even after his law license was revoked in 2015 — to convince various entities, including banks and life insurance companies, to transfer the victim’s money for his use.

Tuesday was not Thomas’ first time behind bars at the local jail. In 2019, after concluding his term as a commissioner at the end of 2018, Thomas served 30 days in jail for contempt of court for failing to comply with a court order to turn over documents from his private law practice related to an elderly client’s power of attorney. He later complied with the records request. A lawsuit related to that case was dismissed. The contempt charge had no connection to his role as an elected official.

The Ohio Board of Professional Conduct in Columbus suspended Thomas’ law license in Ohio in 2015 after he reportedly failed to file an answer to a formal complaint pending before the board. His law license remains suspended in Ohio and West Virginia.

Thomas did not respond to calls seeking comment about the charges.