A man in California arrested in the death of his wife earlier this month reportedly told sheriff's detectives he beat her with a concrete block while claiming it was protecting her from a group of "brutal, powerful" people who had infected him with mayonnaise.

Nathaniel Robertson, 46, has pleaded not guilty to a charge of first-degree murder in the killing of his 57-year-old wife, Lidia. Robertson was arrested on July 12 after his wife found dead with blunt force trauma injuries and blood was discovered splattered at the entrance to their home.

In court documents obtained by KGET, sheriff's deputies said the 57-year-old was discovered the previous day with "major head trauma," surrounded by a large pool of blood with a large concrete block next to her.

CALIFORNIA COUPLE HURT IN 'VERY BRUTAL' ATTACK BY GROUP OF TEENAGERS OUTSIDE THEIR HOME

After his arrest, Robertson told deputies he beat his wife with the concrete block at least four times and killed her in order to keep her from a group of people to "give her compassion and mercy," according to a Kern County Sheriff's Office report obtained by Bakersfield.com.

"I didn't want it to be a painful thing," Robertson told investigators. "I didn't want to hit her a bunch of times, I wanted to end it, I didn't want her suffering."

Robert claims he was infected by mayonnaise that a group he only referred to as "they" put into his leg. The police report obtained by Bakersfield.com said that Robertson claimed the mayonnaise was releasing information to him from the Revolutionary War.

OLE MISS STUDENT ALLY KOSTIAL SEEN WALKING OUT OF BAR HOURS BEFORE MURDER, EX-NEIGHBOR SAYS SUSPECT IS 'ARROGANT'

The 46-year-old also told investigators he was using "ice," also known as methamphetamine, to help him breathe, according to the court documents obtained by KGET.

CLICK HERE FOR THE FOX NEWS APP

Robertson is currently being held at the Lerdo Justice Facility in Bakersfield on $1 million bail, according to jail records. He is scheduled to appear in court July 31 for a pre-preliminary hearing, according to Bakersfield.com.