Gabrielle Swainson Update: Father of missing South Carolina teen doubts she is alive

(CBS/WLTX) COLUMBIA, S.C. - The father of missing South Carolina teen Gabrielle Swainson says he no longer believes his daughter is alive.

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"It's been way too much time," said Alvin Thompson, Swainson's father, according to CBS affiliate WLTX. "Only one person knows that for sure: him."

Thompson was speaking about Freddie Grant, the man accused of kidnapping Gabrielle. Grant was found guilty on Tuesday of having ammunition while being a convicted felon in a separate federal case.

Authorities say they found shotgun shells and .38-caliber bullets when they raided Grant's home in August while searching for evidence in the teen's disappearance,  WLTX reports.

Defense attorney John Delgado says Grant will stay in the Lexington County Detention Center until he's sentenced in April.

Grant is also charged with kidnapping the 15-year-old Columbia girl. Authorities say Grant took the teen Aug. 18.

Complete coverage of the Gabrielle Swainson case on Crimesider