Austin Police say two men—already charged in connection with one murder—also killed a North Austin couple.
Thirty-year-old Shawn Gant-Benalcazar is charged with capital murder.
His accomplice, 49-year-old Timothy Parlin, is charged with home burglary.
Choir teacher Kathy Blair was found dead in her home on December 6.
On December 15, Sidney and Billy Shelton's caretaker found them murdered in their home.
Police arrested the two men about two weeks ago in connection with Blair's murder.
Meanwhile, the Sheltons' neighbors remained on edge.
"It is concerning because you look at everybody a little bit different in the neighborhood now. You look over your shoulder and just wonder what is next," says neighbor Tom Nall.
If you have bought or received anything from Parlin or Gant-Benalcazar, police want to hear from you.
You can call APD's Homicide Tip Line at 512-477-3588.