A Florida man is accused of gunning down his ex-wife and her adult son in front of two young kids after becoming enraged about the lights being left on in the house. “This is absolutely senseless. This is an argument over electricity,” Volusia County Chief Deputy Brian Henderson said of the Sunday shooting in DeLand, according to WESH 2. Michael Williams, 47, was arrested at the scene for allegedly shooting his ex-wife Marsha Williams and her son, 28-year-old Robert Adams, who was visiting with his young children. Henderson said the shooting came after Williams tried to block the pair from using electricity because “he felt that they were leaving the lights on in the house.” Following a confrontation, Williams phoned 911 to report that he’d shot the two, claiming they had been “attacking” him, Henderson said. But according to police, there was no evidence to back up his claim of self-defense. Adams’ children, aged 6 and 6, are thought to have witnessed the killings; they were found in another room when police recovered the victims’ bodies.