FBI spokeswoman Shelley Lynch said in a statement that Quantavious Thompson was taken into custody late Wednesday afternoon. Details on his arrest weren't immediately available Thursday.
Frank Janssen was kidnapped April 5 from his home and driven in a rented hatchback to Atlanta, where he was held for five days before his rescue. Authorities have said the kidnapping was retaliation for the prosecution of a high-ranking Bloods street gang member.
Thompson is scheduled to appear in federal court for a detention hearing Friday morning. Five other suspects have been arrested in the case.
Investigators say they're searching for a seventh suspect, Jakym Tibbs, who's considered armed and dangerous.
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