Robert Flores Carranza, 43, of Ceres, was arrested and booked into the Merced County Jail on Thursday for allegedly attacking someone at an Atwater birthday party with a knife.

According to the Atwater Police Department Lt. Samuel Joseph, the Ceres man was at a birthday party thrown for both his son and niece on Feb. 23 at Ralston Park in Atwater. A family argument turned violent after a domestic argument centered on his recent separation from his wife and children. Those at the party asked Carranza not to start trouble at the family party and then became upset as a result. That's when Carranza allegedly cut Damien Galaviz, 29, on the arm. The wound was serious enough for hospitalization but not life-threatening.

The suspect left the scene before police arrived. On Thursday, four days after the incident, Carranza turned himself into police and saying he only used the knife in self-defense.

The investigation into the incident will be to find the knife. Carranza claims the knife was left at the park but officers did not locate it.