An undocumented immigrant was sentenced to six years in prison Friday for conning a Highlands Ranch woman into buying and handing over gold bars worth more than $126,000 -- her life savings, prosecutors say.

Sagar Patel, 27, pleaded guilty to theft of $20,000 to $100,000 in January, according to court records. Two other theft charges were dismissed.

Patel claimed to be a federal agent when contacted by his 80-year-old victim, who called a phone number included in a pop-up message on her computer warning of a computer virus.

He told the victim that her bank account had been compromised and instructed her to purchase the gold bars and hand them over to a person pretending to be an undercover agent.

The woman recorded the license plate number of a vehicle driven by the fake agent, a detail that investigators eventually used to identify Patel, according to a news release from the 23rd Judicial District.

Patel is subject to an immigration hold by U.S. Immigration and Customs Enforcement and is under investigation for similar crimes in New York and Delaware. The release did not specify Patel's country of origin.

"The victim's bravery and (the Douglas County Sheriff's Office's) relentless efforts helped us to catch this despicable thief and bring him to justice," District Attorney George Brauchler said in the release. "I will continue to warn criminals: if you come here to victimize us, bring a toothbrush. Expect incarceration."