LYONS, Ill. (AP) — Two brothers who told police they buried their mother and sister’s bodies in their suburban Chicago home’s backyard years ago after they died have been released from custody as authorities continue investigating two bodies found buried there.

The brothers, ages 41 and 45, were released on their own recognizance Monday following a 48-hour custody hold. They were taken into custody Saturday after the bodies were found in the backyard in Lyons.

Those bodies have not yet been identified. Lyons Police Chief Tom Herion says that while the brothers have not been charged, they “continue to be the subject of the death investigation.”