(AP) — Omaha police have arrested the sister of a man who is accused of killing four people in August.

Authorities said Thursday that they had charged 23-year-old Erica Jenkins with first-degree murder and weapons charges. Jenkins is accusing of helping her brother kill 22-year-old Curtis Bradford, a man he met in prison, on Aug. 19.

Jenkins’ brother, 26-year-old Nikko Jenkins, is charged with four counts of murder. He is accused of killing Jorge Cajiga-Ruiz and Juan Uribe-Pena on Aug. 11, and shooting to death Andrea Kruger on Aug. 21.

Erica Jenkins was already in custody on other charges. Her younger sister, Lori Sayles, was arrested as an accessory to murder.

Police have also arrested Nikko Jenkins’ uncle, 51-year-old Warren J. Levering.