A 61-year-old man allegedly stabbed Sunday night by his 26-year-old son in Pearl City told police his son suffers from schizophrenia and was off his medication at the time of the attack, according to state court documents.

Valentin John Rudy Bigornia was arrested by Honolulu Police Department officers at 1060 Kameha­meha Highway at 6:30 p.m. Sunday on suspicion of attempted murder in the second degree.

His father, Valentin Quario Bigornia, suffered blunt “injuries to the head and neck, multiple stab/penetrating wounds to the scalp, right forearm, and left elbow, including a penetration into the brain,” and was taken into surgery for his injuries.

He was charged Tuesday and is being held in lieu of $100,000 bail ahead of a preliminary hearing today.

Officers responding at 6:20 p.m. Sunday to a call of a disturbance at an apartment in Pearl City found the 61-year-old Bigornia “exiting the apartment covered in blood, with visible gashes and lacerations to his head and upper body,” according to court records.

The two lived together at the apartment at 1060 Kamehameha Highway in Pearl City from 2002 until 2014, when the 26-year-old Bigornia’s behavior forced his father to move out.

In 2014, Bigornia was diagnosed with schizophrenia and “has not been taking his medication.” His father visited him every day.

At about 6 p.m. Sunday the father went to visit his son to inform him that the “replacement phone was being shipped and come in later.”

The father allegedly told police that his son “hit him with his hands and a guitar stand where he felt pain.”

He also allegedly told officers his son stabbed him, and officers noted that the father “was covered in blood and had multiple stab wounds to his head and arms.”

He suffered “multiple serious injuries from an apparent assault and multiple lacerations,” and city Emergency Medical Services technicians transported him in serious condition to an emergency room.

Officers found the father lying “naked, covered in blood, on the living room floor,” according to court documents. The son was responsive and “complaining of pain in his ankle,” but no other “significant injuries” were found.

During a search of the apartment, officers found a kitchen knife with a silver blade approximately 7 inches in length with a white handle.

In the living room there was a “broken guitar stand” made of metal.

The Elder Abuse Branch of the Department of the Prosecuting Attorney is handling the case. Because the victim is older than 60, the son could receive a longer prison sentence if convicted.