An MS-13 gang member currently serving time for raping an 8-year-old Fairfax County girl has admitted to illegally re-entering the country after being deported, federal officials said Thursday.

Salvador Portillo, 30, of El Salvador, was originally deported in October 2003, after entering the country illegally, federal prosecutors said. He later returned to the United States and was "found," authorities said, in Loudoun County on Nov. 21, 2010. Prosecutors didn't specify why he returned to the country after his initial deportation.

Portillo, authorities say, is a member of MS-13, a violent street gang with ties to El Salvador that has a major presence in the D.C. metropolitan area. He sports a number of MS-13 tattoos, authorities said. Before he fled the area, he lived for a time in Sterling.

Just over 10 days after his return to the United States, on the day after Christmas, Portillo raped the 8-year-old daughter of an acquaintance at a home in Centreville, authorities say. He later fled the area. The U.S. marshals launched a manhunt in response, and Fairfax County issued warrants for his arrest on charges of felony rape and sodomy.

"[Portillo] is a vicious and violent individual," Marshals Deputy Lenny Reynolds said at the time. "Anyone capable of such a horrid and senseless act cannot be allowed to participate in society and must be captured before he has the chance to harm more innocent people."

In February 2011, Portillo was found in Houston and extradited back to Virginia. He's currently serving 25 years in prison after being convicted of the rape and sodomy charges, authorities said.

Earlier this month, Portillo was indicted on illegal re-entry charges and transferred into federal custody, authorities said. He pleaded guilty to the charge in federal court Thursday and faces two years in prison when he's sentenced on Aug. 31.