WASHINGTON (CBSDC/AP) — After spending 22 years in prison, Kirk Odom is a free man. Federal prosecutors say DNA evidence has exonerated Odom who was convicted of a 1981 rape he did not commit.

The U.S. Attorney’s Office on Tuesday joined in a motion to vacate the conviction of 49-year-old Odom, who was sentenced to 20 to 66 years in prison for rape while armed.

Officials say a search of the DNA profile in the FBI’s Combined DNA Index System turned up a match to another man who has previously been convicted of a sex offense. However, at the time there was a six-year statute of limitations on serious sex offenses.

Police say the victim was asleep in her Washington home on Feb. 24, 1981, when a man went into her bedroom and raped her.

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