File Photo: Former Chihuahua state governor Cesar Duarte delivers speech during his annual Government report at the University Cultural Center in Ciudad Juarez, October 10, 2012. REUTERS/Jose Luis Gonzalez

MEXICO CITY (Reuters) - Mexico will present three extradition requests this week for the former ruling party governor of the northern border state of Chihuahua, the attorney general’s office said on Wednesday.

Cesar Duarte, who governed Chihuahua for President Enrique Pena Nieto’s Institutional Revolutionary Party (PRI) between 2010 and 2016, is wanted on graft charges. He is said by his successor in the job to be in the United States.

Acting Attorney General Alberto Elias said his office had received 11 criminal accusations against Duarte in 2017, and after processing them, would draw up the extradition requests.

“This week, we will present three: two for the Chihuahua state attorney general’s office and one for the federal branch,” Elias told reporters.

Elias declined to say where the requests would be directed when asked if they were for the United States. He later said in a radio interview that he could not reveal if Duarte was in the United States lest he infringe due process.

The announcement of the extradition requests comes a day after the PRI’s presidential hopeful, Jose Antonio Meade, who is languishing in third place in opinion polls, urged Mexico to step up efforts to fight rampant corruption and impunity.

The situation in Chihuahua risks keeping attention on alleged PRI graft in the run-up to July’s presidential election. Tackling corruption has become a key campaign issue.

Chihuahua Governor Javier Corral, of the center-right opposition National Action Party (PAN), has taken the lead in trying to bring Duarte back to Mexico to face justice. Corral has repeatedly said Duarte is in the United States.

Last month, Chihuahua’s government announced the arrest by state and federal authorities of Alejandro Gutierrez, a former top PRI finance official. Corral later accused Mexico’s finance ministry of withholding funds to punish his administration for launching an investigation into alleged PRI corruption.