COLUMBIA, S.C. — A second man indicted for scamming millions of dollars from a project to turn warheads into nuclear reactor fuel has pleaded guilty.

Aaron Vennefron, of Ohio, entered the plea Wednesday to one count of conspiracy to commit theft of government funds. Vennefron previously pleaded not guilty to 16 counts. Media outlets report Phillip Thompson, of Augusta, has already pleaded guilty to a similar charge.

Prosecutors say the men created more than $4 million in fraudulent invoices for work they claimed to have done on the mixed-oxide fuel facility at the Savannah River Site. The multi-billion-dollar project is intended to turn weapons-grade plutonium into commercial nuclear reactor fuel.

Vennefron and Thompson have not been sentenced.