NET
26 Then Joab left David and sent messengers after Abner. They brought him back from the well of Sirah. (But David was not aware of it.)
Darby
26 And when Joab was come out from David, he sent messengers after Abner, who brought him again from the well of Sirah; but David did not know it.
KJV
26 And when Joab was come out from David, he sent messengers after Abner, which brought him again from the well of Sirah: but David knew [it] not.