A man from Chicago has been charged with murder, after he allegedly beat an 18-month-old boy to death for urinating on him.

Police charged Martin Alvarado Jr., 23, from the suburb of Cicero, with first-degree murder after his girlfriend’s son, Edwin Eli O'Reilly, was beaten found beaten at his home, Ray Hanania, Cicero town spokesman, told the Chicago Tribune.

Alvarado became enraged after the toddler urinated on him as he changed his nappy. He then repeatedly hit the infant, according to investigators.

Police and an ambulance crew attended the scene after they were alerted that Edwin was unresponsive.

Edwin was rushed to hospital, where he later passed away,CBS Local Chicago reported.

An autopsy concluded that Edwin died due to multiple blunt force injuries, and ruled that his death was a homicide.

Hanania added that Alvarado has made incriminating statements and gave a confession to the crime on camera.