Watts, 30, has pleaded not guilty to charges of attempted armed bank robbery resulting in death and one count of being a felon in possession of a firearm in connection with the May 15 holdup at the First National Bank branch in Cairo.
Authorities allege Watts was armed with a gun and wearing a hooded sweatshirt when he confronted three female employees as they emerged from the bank after closing. Watts had been released from prison two weeks earlier.
The FBI has said the suspect forced the women back inside, but because the bank was closed, he was unable to get any money from the holdup. He ultimately herded the women into an employee lounge and cut each woman's throat, stabbing one woman more than 50 times.
Killed were Anita Grace, 52, of Olive Branch, Illinois, and Nita Jo Smith, 52, of Wickliffe, Kentucky. A 23-year-old woman survived.
Watts was arrested a short time later and remains jailed without bond.