A man already in prison for rape and other crimes is now facing charges for a sexual assault that happened more than two decades ago in St. Louis.

The St. Louis Post-Dispatch reports that DNA evidence links 35-year-old Gary Turner to the rape of a 16-year-old girl that occurred on May 2, 1993. Turner was 14 at the time.

Authorities say the girl was walking home when the suspect pulled a gun, ordered her to a nearby stairwell, and sexually abused her at gunpoint.

Turner has been in prison since 2001, serving a 50-year sentence for convictions that include rape, sodomy, robbery and other crimes.

The new charges say DNA from semen found on the victim's clothing match Turner.

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