On the night of December 5, 1926, Hassell and his wife argued over his involvement with Ferguson's under-aged daughter. Hassell proceeded to strike his wife in the face repeatedly with a ballpeen hammer. After the murder of his wife he moved between each member of the family's beds, using a straight razor and stockings to kill them from youngest to oldest. He woke the two eldest boys and a scuffle ensued, ending with Hassell killing them with a shotgun and an axe. All of the bodies were then stored in the newly dug root cellar by the house.
Hassell claimed to the town he and his family were returning to Oklahoma, and sold all of their belongings in a large yard sale. During the auction a wagon ran over the sinkhole and aroused the suspicion of law enforcement. Soon afterward, Hassell attempted suicide but survived, and excavations revealed the remains in the root cellar.
After Hassell confessed, a short trial was convened and Farwell soon took on a carnival atmosphere, as well as its sister city Texico, New Mexico. On February 2, 1928, George Hassell died in the electric chair, the 27th man executed in the state of Texas.
Hassell had a long history of criminal behavior, including the murder of another family in California, embezzlement and military desertion. According to his testimony his initial act was a crime of passion, the children's deaths being necessary to protect himself. A psychiatric report at the time mentions a complete lack of conscience.