The owner of an industrial staffing company pleaded guilty Wednesday to one count of failing to pay more than $18 million in employment taxes, according to the US Department of Justice’s tax division.

Richard Floyd Tatum Jr., 57, owned Associated Marine & Industrial Staffing Inc., an industrial staffing company that provided temporary labor to businesses in Texas and other states, according to the Department of Justice. Tatum faces a statutory maximum sentence of five years in prison, a period of supervised release, restitution and monetary penalties; sentencing is scheduled for June 1.

Tatum employed approximately 1,000 people — including both internal employees and external employees assigned to work on-site at client locations, according to court documents.

From March 2008 through December 2009, Tatum filed false and untimely employment tax returns for Associated Marin & Industrial Staffing that did not report the company’s external employees, the department reported. In May 2013, Tatum filed untimely returns for the quarters ending in March 2010 through December 2012, reporting his company’s external employees but failing to make any payments. Tatum withheld approximately $12 million in payroll taxes from March 2008 through December 2012, which he did not pay over to the IRS. Tatum also failed to pay $6 million of his company’s contributing share of social security and Medicare taxes during the same quarters. He used the money for his personal benefit, according to the department.

“Failure to pay over employment taxes taken from employee wages is a serious criminal offense,” said Chief Richard Weber of IRS Criminal Investigation. “It not only harms the employees’ future social security and Medicare benefits, it’s stealing from honest taxpayers and the US Treasury. IRS Criminal Investigation will continue to track down those who collect these taxes and use the funds for personal gain.”