(CNN) -- A suspect in a two-state kidnapping plot involving a prosecutor's father made an initial appearance in federal court on Thursday, authorities said.
Quantavious Thompson, 18, was arrested late Wednesday in Atlanta. He waived his right to an identity hearing, FBI spokeswoman Shelley Lynch said. His detention hearing is scheduled for April 23.
Another suspect, Jakym Camel Tibbs, 21, was still being sought, Lynch said.
The FBI has offered a $25,000 reward for the two men, but Lynch said Thursday that it is too soon to determine whether the offer played a role in the capture of Thompson.
Thompson's apprehension marked the sixth arrest in the April 5 abduction of Frank Janssen from his home in Wake Forest, North Carolina. He was rescued by police five days later at an apartment in Atlanta.
The kidnappers sent demands to Janssen's family "for the benefit" of Kelvin Melton, an inmate at Polk Correctional Institution in Butner, North Carolina, according to an affidavit in support of a search warrant related to criminal complaints against the defendants.
Janssen's daughter, Colleen Janssen, is an assistant district attorney in Wake County and had prosecuted Melton, officials said. Melton is serving a life sentence without parole.
Authorities said they traced a call to Melton's prison cell, from where he communicated with the kidnappers. The FBI said the group planned to kill Janssen and bury him at the apartment complex, which is near the federal penitentiary in Atlanta, according to CNN affiliate WXIA.
CNN's Vivian Kuo and Ralph Ellis contributed to this report.