SEFFNER, Fla. (WFLA) — A second person was arrested in connection to the “cold-blooded” murder of a 22-year-old mother who was shot and killed outside her home in Seffner.

Hillsborough deputies said 32-year-old Phillip Stapleton was arrested Monday for principal to murder in the first degree and conspiracy to commit first-degree murder in connection to the murder of Ashley Voss on July 20.

Hillsborough County Sheriff Chad Chronister previously said Voss was raising her two small boys when she was shot and killed in her own car after returning home from her job at a local restaurant.

Less than 24 hours after the murder, deputies arrested the accused shooter, 32-year-old Aurelio Diaz.

“Diaz had no motive to shoot my granddaughter,” Voss’s paternal grandmother, Rhonda said. “He barely knew her. He knew of her. She knew of him but only because he and the baby’s father were very good friends.”

“[Stapleton’s] arrest is another example of the tenacity with which our detectives continue to pursue leads to crimes here in Hillsborough County,” Chronister said. “Our team works each tip relentlessly to remove any danger they can to the community that we serve.”

Stapleton’s exact actions in connection to the murder remain unclear.