After the employer of Cristhian Bahena Rivera, the man charged with first-degree murder in the death of University of Iowa student Mollie Tibbetts, told reporters Wednesday that Rivera used a false name to work at Yarrabee Farms, the Iowa Department of Transportation on Thursday confirmed no Iowa credentials had been issued to Rivera under any name.

“The Iowa DOT has reviewed our records and confirmed that no Iowa license or credential was issued to Cristhian Bahena Rivera, either under that name or any alternate name bearing his likeness, and we have no license history for him,” the DOT statement read.

So long as a person “possesses and presents an Iowa-issued credential,” the DOT is involved in the employment-verification process in which an employer may enter an employee’s credential information presented as proof of identity and employment authorization into the E-Verify system.

According to the DOT, the review used the department’s facial recognition system to “compare his likeness to all images on record” and confirm that he did not obtain a state-issued license or ID “under a different or false name.”

Iowa law is consistent with the federal REAL ID Act, which sets standards for issuing identification. The DOT said the law “prohibits us from issuing any type of driver’s license or identification card to a person who is an undocumented immigrant” while authorizing the department to issue such identification to those considered to be “a temporary foreign national.”

The DOT defined a temporary foreign national as a person whose presence in the U.S. is authorized, as determined by the U.S. Customs and Immigration Service and other government agencies after the person presents verifiable documents. An undocumented immigrant, said the DOT, has “no such lawful status” and “is not eligible for an Iowa license or ID.”

“We stand with the countless others who are saddened by this tragic event and are keeping the friends and family of Mollie Tibbetts in our hearts,” the DOT statement read.

Reports surfaced after Rivera’s initial court appearance Wednesday that the 24-year-old man worked on Yarrabee Farms near Brooklyn, Iowa, where Tibbetts, 20, disappeared July 18 under a false name since 2014.

Authorities announced Tuesday in Montezuma that Rivera got out of his car while Tibbetts was running and ran beside her before abducting and killing her. They said Tibbetts was believed to have been found dead in rural Poweshiek County and that Rivera, who they said was an undocumented immigrant, led law-enforcement officials to the location of her body.

Rivera’s attorney, Allan Richards, has indicated he is prepared to argue that Rivera was in the country legally.

The judge set Rivera’s bond at $5 million cash only. If released on bond, he wouldn’t be allowed to leave Poweshiek County.

Rivera is set to appear in court again Aug. 31 at 2 p.m. in Poweshiek County.