Mexico opposition party chides ex-governor in drug probe MEXICO CITY (Reuters) - Mexico's opposition party, leading by double digits in presidential polls, on Wednesday said a former governor must face up to charges in the United States of accepting millions of dollars from drug cartels. In an effort to contain what is likely to become a hot campaign issue, the Institutional Revolutionary Party (PRI) said they are deciding if Tomas Yarrington, former governor of the state of Tamaulipas, should be thrown out of the party. On Tuesday, U.S. prosecutors moved to seize millions of dollars' worth of real estate in Texas that Yarrington allegedly brought with drug money. "Yarrington has to face justice in the country where he is being accused," the PRI said in a statement. The PRI does not cover up impunity under any circumstances. The PRI's candidate for president, Enrique Pena Nieto, has a commanding lead ahead of the July 1 vote but is fighting off attacks from rivals who say a win for the party that ruled for seven decades would be a return to Mexico's corrupt past. Yarrington served as governor of Tamaulipas on the U.S.-Mexico border from 1999 to 2005. The accusations against him were brought in two civil suits but he has not been charged criminally. " (Yarrington) acquired millions of dollars in payments while holding elected office from large-scale drug organizations," one complaint filed in a U.S. district court in southern Texas said. "He used his illicit income from his political years to become a major real estate investor through various money laundering mechanisms," the court documents said. Yarrington was also the mayor of Matamoros, Tamaulipas, from 1992 to 1995, and sought nomination for the Mexican presidency in 2005. One of the seized properties was a condo in the resort community of South Padre Island, at the southern tip of Texas, and the other was a larger site in San Antonio, prosecutors said. Yarrington's lawyer has denied the properties belong to him, and called the charges "false allegations and false rumors." Yarrington has not been arrested or detained, said Angela Dodge, a spokeswoman for the U.S. Attorney's Office. Mexican media reported that he was in Houston. Tamaulipas, across the Rio Grande from Texas, is one of the country's most violent drug trafficking corridors. Conservative President Felipe Calderon sent thousands of federal police and soldiers to take on the cartels after taking office in late-2006. However, drug murders have soared since then, reaching around 55,000 during the administration. Calderon is prohibited by the constitution from running for re-election but his National Action Party (PAN) candidate Josefina Vazquez Mota is trailing by up to 20 points in the polls. The PRI has gained much support by promising to restore security to the streets. Vazquez Mota has hit back, accusing the PRI of being complicit with drug gangs and said they may try to cut deals with cartels to lower murder rates. "Yarrington is the face of the corrupt PRI that hasn't gone away," Vazquez Mota told local radio. This is what we can't allow to happen again in our country. The PAN, which broke the PRI's 71-year hold on power in 2000, is trying to shine a spotlight on a string of recent graft investigations against PRI officials. The former treasurer of the state of Coahuila - who once worked for former PRI chairman Humberto Moreira - is also a target of a U.S. money laundering probe. Additional reporting by Lizbeth Diaz in Mexico City and Corrie MacLaggan in Austin; Editing by Jackie Frank