Police: Person Of Interest In Girls' Vanishing

GAITHERSBURG, Md. (AP) -- A convicted child sex offender has been identified as a person of interest in the 1975 disappearance of two sisters who never returned home from a Montgomery County shopping mall, police said Monday.

The man, whose name was not released, is imprisoned in another state and is believed to have been at the mall on the day the girls disappeared.

Authorities expect to release more information about the case on Tuesday, including photographs, and are seeking the public's help to learn more about the man and his activities during that time, said Capt. Jim Daly, a Montgomery County police spokesman. Police described the man as a person of interest but would not elaborate. He is believed to have traveled extensively throughout the United States.

The announcement could represent a significant break in the investigation into the March 25, 1975, disappearance of 12-year-old Sheila Lyon and her 10-year-old sister Katherine. The girls went missing after walking to a nearby shopping center, then known as the Wheaton Plaza. Investigators interviewed witnesses who saw the sisters at the mall before their disappearance.

The investigation triggered an extensive search in the state and generated many tips, but the case has remained unsolved.

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