Attorney General Marisela Morales said Tomas Yarrington Ruvalcaba faces charges of "crimes against health," the San Antonio Express-News reported. The newspaper said the term is one used by Mexican officials for crimes involving the cartels.
Yarrington, who also served in Congress and as mayor of Matamoros, a city on the U.S. border, has left Mexico. He was expelled by the Institutional Revolutionary Party in May.
"At this moment, we have no information as to where he might be," Morales said.
Yarrington and his alleged associates are under investigation for alleged money laundering by agencies in Mexico and the United States. Tamaulipas is bordered on the north by Texas.
Antonio Pena Arguelles, a businessman and rancher in Texas, was arrested in February at his home in Stone Oak, an upscale development in San Antonio. Fernando Alejandro Cano Martinez, an alleged Yarrington associate, was indicted in May by a federal grand jury in Brownsville.
Yarrington has used Twitter and interviews with Mexican reporters to proclaim his innocence.