Investigators don't believe a Cobb County sheriff's deputy knew his son was a suspect in a double homicide. But the deputy definitely found out when FBI agents arrived to arrest the 19-year-old at a home near Acworth.

Federal investigators tracked Elijah Naitron Valentin from North Carolina to his father’s home in Cobb County, where he was arrested Thursday. Valentin has been charged with two counts of murder in the Dec. 2 deaths of two cousins, according to Greensboro, N.C., police. He is the second suspect charged in the case.

“Valentin’s arrest is the result of an extensive joint investigation involving the FBI, local law enforcement officials from Georgia, and the Greensboro Police Department,” Greensboro police posted on Facebook.

Ernest Lemark Cuthbertson, 23, and Jeffrey Devine Hampton, 44, were shot to death following a verbal dispute, police said. Valentin and Cuthbertson were acquaintances, but investigators have not determined what led to the altercation. Chauncey Jamal Slade, 17, was previously arrested and charged with murder, according to police.

Valentin’s father is a deputy based at the Cobb jail, where his son was being held Tuesday while awaiting extradition. The two are not allowed to be in contact with each other, a spokesman for the sheriff’s office said.