The U.S. Attorney's Office for the Southern District of Ohio announced that Brian Michael Rini pleaded guilty in U.S. District Court Wednesday.
Rini was charged with making false statements to a federal agent after he was found wandering the street in Newport, Kentucky, in April 2019.
Rini told officers that he was Timmothy Pitzen, a 6-year-old Aurora boy who went missing in 2011.
WATCH: Timeline of Timmothy Pitzen case
Investigators said Rini claimed to have been physically and sexually abused since being kidnapped in 2011 and had just broken free of his captors near Cincinnati when he was found in Newport.
Rini, who was 23 at the time, claimed he was 14 and that he had escaped from a hotel room where two men had been holding him captive, federal officials announced in a statement Wednesday.
RELATED: Timmothy Pitzen Update: Brian Rini, man accused of claiming to be missing Aurora boy, charged with lying to FBI
After he was approached by officers, Rini complained of abdominal pain and was taken to Cincinnati Children's Hospital, federal officials said. There, Rini met with FBI officers investigating the case.
He refused to provide his fingerprints but later agreed to DNA testing, which confirmed Rini's identity, the U.S. Attorney's Office for the Southern District of Ohio said.
Investigators learned that Rini had recently been released from an Ohio prison.
Once confronted, Rini told law enforcement officers that he had watched a story about Timmothy Pitzen on ABC's 20/20 and said he wanted to get away from his family, authorities said.
RAW VIDEO: Timmothy Pitzen last seen on surveillance video
Investigators later learned that Rini had previously portrayed himself as a juvenile sex trafficking victim on two separate occasions, the U.S. Attorney's Office said.
Aggravated identity theft is punishable by a mandatory two-year prison sentence, federal officials said.
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