Doris Toler, 48, was shot multiple times with a rifle inside a house on Harris Street.
Police initially took six people into custody.
They now say Alphonza Fellows, 54, is responsible for the shooting.
Police say the murder appears to be the end result of a dispute between two families.
"It appears that two families have been arguing for a couple of days over some minor incident, and it just escalated into violence and we have the tragic ending that we have now," says Lt. R.J. Cuddington of the Smithfield Police Department.
Charges against Fellows are still pending.